Answer:
-397Step-by-step explanation:
This may look daunting, but let us approach it step by step.
Step 1: Remove the Parenthesesmultiply 1/10 by x - 3
0.1x - 0.3 = -40
Step 2: Add 0.3In algebra, the goal is always to undo all the operations and get back to the original problem so that the mystery value can be determined. In this case since 0.3 was removed, we must add it back.
0.1x = -39.7
Step 3. Divide by 0.10.1x/0.1 = x
39.7/0.1 = -397
Step 4. Preliminary AnswerAnswer seems to be B. -397, but we should still check it.
Step 5: Check0.1(-397) - 0.3 = -40
-39.7 - 0.3 = -40
-40 = -40 Correct
If the answer was incorrect, this would show that there had been a flaw in our calculations. But everything checks out, so we are done!
Step 6: Final AnswerOur final answer is B. -397.
PLEASE MARK BRAINLIEST
Answer:
The answer is -397
Step-by-step explanation:
Which strategy would not correctly solve this story problem? Luke buys a muffin and glass of juice each Monday for breakfast. Each muffin costs $3 and each glass of juice costs $2. How much money will Luke spend for breakfast on 6 Mondays? A. Make a table. Week 1 2 3 4 5 6 Total ($) 5 10 15 20 25 B. Translate into an equation. (3 × 2) + 6 = d C. Use objects to represent the problem. Set out 6 small cups. Use coins to represent dollars. Add $2 + $3 to get the amount spent each Monday ($5). Put that number of coins into each cup. Count the number of coins in the cups. D. Use logical reasoning. In 1 week Luke spent $3 for a muffin plus $2 for juice for a total of $5. So to figure out how much Luke spent in 6 weeks, multiply $5 by 6.
Answer:
The answer is D.
Step-by-step explanation:
Each Monday, Luke spends $5 ($3 for the muffin, $2 for the juice). To figure out how much he spends in 6 weeks, you multiply $5 by 6. Hope this helps! :)
An object is launched from a platform. It's height (in meters), x seconds after the launch, is modeled by: h(x) = -5x^2 + 20x + 60. What is the height of the object at the time of launch?
Answer:
60 meters
Step-by-step explanation:
The standard form for parabolic motion is
[tex]h(x)=-5x^2+v_{0}x+h_{0}[/tex]
where [tex]v_{0}[/tex] is the initial upwards velocity and [tex]h_{0}[/tex] is the initial launching height. If I am understanding your question, this is what you are looking for. So the height AT the time of launch was 60 meters.
Answer:
The height of the object at the time of the launch is [tex]60m[/tex]
Step-by-step explanation:
We know that the height in meters, x seconds after the launch is modeled by the following function :
[tex]h(x)=-5x^{2}+20x+60[/tex]
For example, after [tex]x=3s[/tex] from the launch the height of the object is :
[tex]h(3s)=-5.(3^{2})+20.(3)+60=75[/tex]
[tex]h(3s)=75m[/tex]
If we want to know the height of the object at the time of the launch we will need to find the height of the object at [tex]x=0s[/tex] because that is the instant where the object is launched.
If we use [tex]x=0s[/tex] in [tex]h(x)[/tex] ⇒
[tex]h(0s)=-5.(0^{2})+20.(0)+60=60[/tex]
We find that the height of the object at the time of launch is [tex]60m[/tex]
Find the value of x, rounded to the nearest tenth
Answer:
x = 12.5
Step-by-step explanation:
The given triangle is a right angle triangle.
We cannot use the Pythagoras theorem as the lengths of all sides are not known. We will use triangular ratios here to solve the given problem.
As it is clear from the diagram that x is the hypotenuse of the triangle and 11 is the length of the base. We will use a ratio in which base and hypotenuse are used.
So,
cos θ= base/hypotenuse
cos 28=11/x
x=11/cos28
x=11/0.8829
x=12.45
Rounding off to nearest 10
x=12.5
The value of x is 12.5 in the triangle by using cosine function, option B is correct.
We need to find the value of x in the triangle.
The given triangle is a right angles triangle.
We find value of x by using cosine function.
Cosine function is a ratio of Adjacent side and hypotenuse.
Cosθ = Adj side/hypotenuse.
Here θ = 28 degrees.
Adjacent side = 11.
Hypotenuse = x.
Plug in these values in above formula:
Cos28 degrees = 11/x
x=11/cos28
x=11/0.882
x=12.47
x=12.5
Hence, the value of x is 12.5.
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20 POINTS PLEASE HELP!!!!!!!
Answer is y = 3sin2(x - pi/4).
Please help me with this
Answer:
Step-by-step explanation:
Center
x = 5
y = - 3
r = 4
(x - 5)^2 + (y - - 3)^2 = 4^2
(x - 5)^2 + (y + 3)^2 = 16
Which of the following functions has the largest value when x = 3?
c(x) = 3x2 + 5x + 22
j(x) = 12x
a(x) = 9x
All the functions are equal at x = 3.
c(x)
j(x)
a(x)
Answer:
c(3) is the largest
Step-by-step explanation:
For positive values of x, j(x) > a(x), so the comparison is between c(x) and j(x).
Without evaluating the functions, you can subtract 5x from them to get ...
c'(x) = c(x) -5x = 3x² +22
j'(x) = j(x) -5x = 7x
Now the question is whether c'(3) is larger than j'(3). The latter is ...
j'(3) = 7·3 = 21
Since c'(3) has an added constant of 22 and x² will be positive, we know that ...
c(3) > j(3) > a(3)
The function with the largest value at x=3 is c(x).
_____
You can, of course, simply evaluate the functions:
c(3) = (3·3 +5)·3 +22 = 14·3 +22 = 42 +22 = 64j(3) = 12·3 = 36a(3) = 9·3 = 27c(3) > j(3) > a(3) . . . . . . . c(3) is the largest
Answer:
It’s D
Step-by-step explanation:
a(x)
Natasha is driving at a rate of 4 miles every 3 minutes how fast is Natasha driving
Answer:
80 mph
Step-by-step explanation:
Since Natasha is driving at a rate of 4 miles every 3 minutes, we are asked to find her speed in mph. Since there are 60 minutes in an hour, we can make a proportion: 4/3 = x/60. Solving for x, we get x to be 80. So Natasha is driving at 80 miles an hour.
Answer:
80 miles per hour
Step-by-step explanation:
60 / 3 = 20
4 x 20 = 80
William put $500 into a savings account that earned 2% simple intrest after 3 years how much interest did william earn
Answer:
$30
Step-by-step explanation:
$500 x 0.02 x 3 = 30
Answer:
$30 is the answer
Which equation, when graphed, has x-intercepts at (2, 0) and (4, 0) and a y-intercept of (0, –16)?
f(x) = –(x – 2)(x – 4)
f(x) = –(x + 2)(x + 4)
f(x) = –2(x – 2)(x – 4)
f(x) = –2(x + 2)(x + 4)
Number 3 is the correct answer
Tell me if you want further explanation
Answer:
f(x) = –2(x – 2)(x – 4)
Step-by-step explanation:
In the first two possible answer choices we have a 2 and a 4, whose product is 8, whereas we need a y-intercept of -16. So omit the first two choices.
If the x-intercepts are at (2, 0) and (4, 0), the corresponding factors must be (x - 2)(x - 4), so the third answer, f(x) = –2(x – 2)(x – 4), must be the correct one.
i need answer for these questions please
QUESTION 5
The given equation is:
[tex] \frac{5}{a + 3} = \frac{3}{a - 2} [/tex]
Cross multiply;
[tex]5(a - 2) = 3(a + 3)[/tex]
Expand:
5a-10=3a+9
Group similar terms:
5a-3a=9+10
2a=19
Divide both sides by 2
[tex]a = \frac{19}{2} [/tex]
[tex]a = 9\frac{1}{2} [/tex]
The correct answer is C.
QUESTION 7
The given equation is:
[tex] \frac{3}{y - 2}= 8[/tex]
There is an invisible 1 in the denominator on the RHS.
[tex] \frac{3}{y - 2}= \frac{8}{1} [/tex]
Cross multiply:
[tex] 3\times 1 = 8(y - 2)[/tex]
Expand:
[tex]3= 8y - 16[/tex]
Group similar terms,
[tex]3 + 16 = 8y[/tex]
[tex]19 = 8y[/tex]
Divide both sides by 8.
[tex]y = \frac{19}{8} [/tex]
[tex]y = 2 \frac{3}{8} [/tex]
The correct answer is C.
QUESTION 8
The given fraction is:
[tex] \frac{ {w}^{2} + 5w + 6}{ {w}^{2} - w - 12 } [/tex]
Factor both the numerator and the denominator to obtain:
[tex] \frac{(w + 3)(w + 2)}{(w + 3)(w - 4)} [/tex]
Cancel the common factors;
[tex]\frac{w + 2}{w - 4} [/tex]
The correct answer is B.
QUESTION 9
The given expression is;
[tex] \frac{3m}{m - 6} \times \frac{5 {m}^{3} - 30 {m}^{2} }{5 {m}^{2} } [/tex]
Factor the numerator of the second fraction.
[tex]\frac{3m}{m - 6} \times \frac{5 {m}^{2}(m - 6)}{5 {m}^{2} }[/tex]
Cancel the common factors,
[tex] \frac{3m}{1} [/tex]
[tex] = 3m[/tex]
The correct answer is D.
QUESTION 10
The given expression is:
[tex] \frac{7x + 21}{ {x}^{2} + 5x + 6} \div \frac{x + 6}{x + 2} [/tex]
Multiply by the reciprocal of the second fraction.
[tex]\frac{7x + 21}{ {x}^{2} + 5x + 6} \times \frac{x + 2}{x + 6} [/tex]
Factor the first fraction to get:
[tex]\frac{7(x + 3)}{ (x + 2)(x + 3)} \times \frac{x + 2}{x + 6} [/tex]
Cancel the common factors:
[tex] \frac{7}{x + 6} [/tex]
The correct answer is A.
If the volume of a rectangular prism is 200 cubic units, and the area of the base is 16 square units, what is the height of the prism?
Answer:
It is 12.5
Step-by-step explanation:
It is because the formula of finding the volume of a rectangular prism is area of the base x height.
So you do 200 divided by 16 (Which is the height) which equals 12.5
Answer:
The height of the prism is 12.5 units.
Step-by-step explanation:
Volume formula: V = (length)(width)(height)
or V = (area of base)(height)
Here, we want to calculate the height. The appropriate formula is
(height) = (volume) / (area of base) = (200 units³) / (16 units²) = 12.5 units
The height of the prism is 12.5 units.
PLEASE HELP!
Find the function inverse ,f-1(x) , of y = 2x + 1.
Answer:
[tex]f^{-1}(x)=\frac{x}{2}-\frac{1}{2}[/tex]
Step-by-step explanation:
It is called an inverse or reciprocal function of [tex]f[/tex] to another function [tex]f^{-1}[/tex] that fulfills that:
If [tex]f(a)=b[/tex], then [tex]f^{-1} (b)=a[/tex]
To calculate the inverse of the function [tex]y=2x+1[/tex]
[tex]f(x)=y[/tex]
So, rewritting the function
[tex]f(x)=2x+1[/tex]
Changing the x for y
[tex]x=2y+1[/tex]
Let's clear y
[tex]y=\frac{x-1}{2}[/tex]
Ordering the function above
[tex]y=\frac{x}{2}-\frac{1}{2}[/tex]
So, the inverse of the function [tex]f(x)=2x+1[/tex] is:
[tex]f^{-1}(x)=\frac{x}{2}-\frac{1}{2}[/tex]
.
Can somebody help me?
Answer:
6
Step-by-step explanation:
Arc length = radius * central angle
s = rθ
A circle is 2π radians, so 1/3 of that is 2/3 π.
Given that s = 12 and θ = 2/3 π:
12 = r (2/3 π)
r = 18/π
r ≈ 6
A cylinder has a radius of 3 cm and a height of 24 cm. What is the area of the rectangle made by the circumference and height of this cylinder?
A) 508.68 cm2
B) 480.42 cm2
C) 452.16 cm2
D) 84.78 cm2
Answer:
Option C. [tex]452.16\ cm^{2}[/tex]
Step-by-step explanation:
step 1
Find the circumference
The circumference of a circle is equal to
[tex]C=2\pi r[/tex]
we have
[tex]r=3\ cm[/tex]
[tex]\pi=3.14[/tex]
substitute
[tex]C=2(3.14)(3)=18.84\ cm[/tex]
step 2
Find the area of the rectangle made by the circumference and height of the cylinder
The area of the rectangle is equal to
[tex]A=C*h[/tex]
substitute the values
[tex]A=(18.84)(24)=452.16\ cm^{2}[/tex]
Answer:
C
Step-by-step explanation:
Farmer Bob has pigs and chickens. He has 37 animals, and there are 124 legs among them altogether. How many chickens does Bob have? A. 25 B. 4 C. 12 D. –4
C. bc chickens have two legs each making it 12 chickens times 2 legs equal 24 plus the remaining 25 animals (pigs) would be 25x4=100+24 chicken legs = 124
For this case we have that the pigs have 4 legs while the hens have 2.
We propose a system of equations:
x: Variable representing the number of pigs
y: Variable representing the number of chickens
[tex]x + y = 37\\4x + 2y = 124[/tex]
We multiply by -4 the first equation:
[tex]-4x-4y = -148[/tex]
We add the equations:
[tex]-4x-4y = -148\\4x + 2y = 124\\-4y + 2y = -148 + 124\\-2y = -24\\y = \frac {24} {2}\\y = 12[/tex]
So, there are 12 chickens.
[tex]x + 12 = 37\\x = 37-12\\x = 25[/tex]
There are 25 pigs.
ANswer:
25 pigs
12 chickens
Option C
W = -0.5m + 16Henry's water bottle is leaking at a constant rate. The amount of water, W in ounces, that is left in the water bottle after leaking for m minutes is given by the equation above. What does the −0.5 mean in the equation?The water bottle loses 2 ounces of water per minute
The water bottle loses 0.5 an ounce of water per minute
The water bottle has 0.5 an ounce of water in it at the start
0.5 of the water has leaked from the water bottls in one minute
Answer:
• The water bottle loses 0.5 an ounce of water per minute
Step-by-step explanation:
The definition of the variables tells you that m stands for minutes and that W stands for the water remaining in the bottle. So, the -0.5m in the equation has the effect of reducing the remaining water by 0.5 each time m increases by 1. That is, there are 0.5 fewer ounces of water after each additional minute: the bottle loses 0.5 ounces per minute.
Which choice is equivalent to the fraction below? Hint: Rationalize the denominator and simplify.
Please show work.
Answer:
[tex]\boxed{\text{D. }3\sqrt{2}}[/tex]
Step-by-step explanation:
Multiply numerator and denominator by √2
[tex]\dfrac{6}{\sqrt{2}} = \dfrac{6}{\sqrt{2}} \times \dfrac{\sqrt{2}}{\sqrt{2}}\\\\= \dfrac{6\sqrt{2}}{2}\\\\= \boxed{3\sqrt{2}}[/tex]
Answer: D. [tex]3\sqrt{2}[/tex]
Step-by-step explanation:
The given fraction : [tex]\dfrac{6}{\sqrt{2}}[/tex]
Here, the denominator is in radical form which makes it not an simplified form.
So , we rationalize it by multiplying [tex]\sqrt{2}[/tex] to the numerator and the denominator , we get
[tex]\dfrac{6}{\sqrt{2}}\times\dfrac{\sqrt{2}}{\sqrt{2}=\dfrac{6\sqrt{2}}{2}}\\\\=\dfrac{2\times3\times\sqrt{2}}{2}\\\\=3\sqrt{2}[/tex] [Cancel 2 from the numerator and the denominator.]
Hence, the choice is equivalent to the given fraction = [tex]3\sqrt{2}[/tex]
Hence, the correct option is D. [tex]3\sqrt{2}[/tex]
Which statement is correct for 45-45-90 triangles?
Final answer:
The correct statement for a 45-45-90 triangle is that the legs are equal in length, and the hypotenuse is the length of a leg multiplied by √2, following from the Pythagorean Theorem.
Explanation:
The correct statement for 45-45-90 triangles is that they are special right triangles featuring two 45-degree angles and one 90-degree angle. In such triangles, the lengths of the legs are equal, and the length of the hypotenuse is √2 times the length of a leg. This arises from the fact that in a 45-45-90 triangle, the two legs opposite the 45-degree angles are congruent, which also means that their corresponding sides are in a ratio of 1:1, and the hypotenuse can be found by multiplying one of the legs by √2.
This is a consequence of the Pythagorean Theorem where, for a right-angle triangle with sides 'a' and 'b' and hypotenuse 'c', the relationship is c^2 = a^2 + b^2. Since 'a' and 'b' are equal in a 45-45-90 triangle (let's call each side 's'), the equation simplifies to c^2 = 2s^2, implying c = s√2. This ratio is essential to understanding the properties of these triangles and is used frequently in various geometry and trigonometry problems.
3 less than 3 times a number is 12, what is it?
The number is 3.
3x3 is 9, which is 3 less than 12.
Answer:
The number is 5.
Step-by-step explanation:
12 plus 3 is 15.
5 x 3 = 15
15 - 3 = 12
3 less than 3 times a number is 12.
It sounds like 3 less from a number IS 12. So adding 3 to 12 will get 15, and 15 divided by 3 equals 5.
I hope this is correct and that it helps! :)
Please help me out with this
Answer:
162.4 in²
Step-by-step explanation:
The area (A) of a regular octagon is
A = [tex]\frac{1}{2}[/tex] perimeter × apothem
here perimeter = 8 × 5.8 = 46.4 in, hence
A = 0.5 × 46.4 × 7 = 162.4 in²
TAKE ALL MY POINTS PLEASE HELP ME
The high temperatures for Dallas, Texas in June 1985 and June 2013 are shown. Use the data to create a comparative dot plot and comparative box plot and use them to compare the weather then and now. Remember to use at least two module vocabulary words in your responses.
1. Create a comparative dot plot for the data sets.
2. Assess the degree of overlap between the data sets and compare the shapes, centers, and spreads of the two groups using the comparative dot plot.
3. Create a comparative box plot for the data sets.
4. Assess the degree of overlap between the data sets and compare the shapes, centers, and spreads of the two groups using the comparative box plot.
1. First two pictures below.
2.Both of them have large clusters that are a couple spaces away. The range is greater with June 2013.
3. Second two pictures below. The third pic is June 1985 and fourth is June 2013.
4. The spread is smaller for June 1985. The boxes are seem to have the same proximity to each other which shows a tight center between the two box plots.
May be to late, but I'll post my answers to your questions anyway :)
Final answer:
Without specific temperature data, we cannot create the comparative dot plots and box plots requested by the student. Instructions have been provided on how to create and analyze them once the data is available.
Explanation:
To answer the student's question about comparing the high temperatures for Dallas, Texas in June 1985 and June 2013 using comparative dot plots and comparative box plots, we first need the individual temperature data for each June to create these graphs. Unfortunately, without the specific data, we are unable to create the plots.
However, we can discuss how to approach this problem. To create a comparative dot plot, you would list the temperatures for each data set on a horizontal line, each set represented by dots. Then, assess the degree of overlap by visually inspecting where the dots from both data sets lie in relation to each other. Compare their shapes, centers, and spreads by observing the clustering of the dots, the location of the “middle” of the dots, and how far the dots extend out from the center.
For the comparative box plot, you would draw two box plots on the same axis. A box plot displays the minimum, first quartile, median (or second quartile), third quartile, and maximum. Assess the degree of overlap by comparing where the boxes and whiskers of the plots are positioned in relation to each other, again paying attention to the centers (medians), spreads (interquartile ranges), as well as the overall range of data. Both types of plots can help ascertain whether the high temperature in June of each year was significantly different from the other, and how each year's temperatures compare to the historical average.
When we solving a formula for a specific variable we must ______ it
Answer:
you must solve the question.
Step-by-step explanation:
it would be when we're solving a formula for himself a variable we must solve it.
Answer:
isolate
Step-by-step explanation:
You have 6 reindeer, Prancer, Rudy, Balthazar, Quentin, Jebediah, and Lancer, and you want to have 3 fly your sleigh. You always have your reindeer fly in a single-file line. How many different ways can you arrange your reindeer?
Answer:
120 ways.
Step-by-step explanation:
We have been given that you have 6 reindeer, Prancer, Rudy, Balthazar, Quentin, Jebediah, and Lancer, and you want to have 3 fly your sleigh. You always have your reindeer fly in a single-file line.
We will use permutation formula to solve our given problem as:
[tex]_{r}^{n}\textrm{C}=\frac{n!}{(n-r)!}[/tex]
[tex]_{3}^{6}\textrm{C}=\frac{6!}{(6-3)!}[/tex]
[tex]_{3}^{6}\textrm{C}=\frac{6\cdot 5\cdot 4\cdot 3!}{3!}[/tex]
[tex]_{3}^{6}\textrm{C}=6\cdot 5\cdot 4[/tex]
[tex]_{3}^{6}\textrm{C}=120[/tex]
Therefore, you can arrange your reindeer in 120 different ways.
Lia is comparing her check register to her bank statement, and the ending balances don't seem to match. To check her register for transposing errors, she needs to subtract the balances and _____ the difference _____.. . A.divide; by 9. B.multiply; by 9. C.subtract; from 9. D.add; to 9. . @Loveiskey18
Answer: Divide by 9 ------- APEX
Step-by-step explanation:
i got it wrong and that was the right answer eiahhh
To check her register for transposing errors, Lia needs to subtract the balances and divide the difference by 9. so. the correct option is A.
How to divide a quantity into finite equal parts?Suppose that there are k things which are to be divided in P parts, then
K÷ P will give the amount that each one of P parts would get from k, which will make equal distribution of k things in P parts.
Lia is comparing her check register to her bank statement, and the ending balances don't seem to match.
To balance her check register, Lia needs to subtract the balances and divide the difference by 9.
If entries in her bank statement do not appear in her check register or vice versa.
To check her register for transposing errors, Lia needs to subtract the balances and divide the difference by 9. so. the correct option is A.
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A baker made 5 pounds of dough . He used 4/9 of the dough to make sandwich rolls . How much of the dough is left over
There’s twenty over nine pounds
Answer:
2.22..
Step-by-step explanation:
First you divide four by nine to get 0.44..
then you multiply that by five to get your answer which is 2.22.. , Two Point Two repeating, 20/9, 2 2/9 or Two and Two Ninths.
help me with this thank you
It’s a frequency table, you find the middle number from the prices of mail received and you would multiply it. Not sure what with but if you search on Google Frequency tables there should be a good explanation.
Hope this helped you!
A taxpayer had a taxable income of $14,200, and his spouse had a taxable income of $13,700. If they wish to file their tax return jointly, which tax bracket will they fall into?
A. 0%
B. 10%
C. 38%
D. 15%
Answer:
15% apex confirmed
Step-by-step explanation:
The taxpayer and his spouse, with a combined taxable income of $27,900, will fall into the 15% tax bracket for a married couple filing jointly for the 2020 tax year.
Explanation:The subject of this question is the United States Federal Income Tax Brackets. The taxpayer and his spouse have a combined taxable income of $14,200 + $13,700 = $27,900. For the 2020 tax year, a married couple filing jointly with taxable income between $0 and $19,750 fall in the 10% tax bracket, while those with taxable income between $19,751 to $80,250 are in the 15% tax bracket. So, the taxpayer and his spouse, with their combined taxable income, will fall into the 15% tax bracket. Their taxable income exceeds the threshold for the 10% tax bracket and does not reach the threshold for the 38% bracket. Please note, it's important to stay informed about tax brackets as they can change annually.
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YTV.ov
INSIDE SALES Jessica Parker is a sales associate at JC Penney and is paid $13.60 per
hour for straight time and time and a half for all hours over 40 worked in a week. Find her
gross earnings for a week in which she worked 52 hours.
Answer:
is b
Step-by-step explanation:
WILL GIVE BRANLIEST! :(
I am so bad at proofs!
It is all on the picture <3
Step-by-step explanation:
The triangles are congruent isosceles, therefore LM ≅ MN ≅ NO ≅ OL.
All four sides are equal, so be definition, quadrilateral LMNO is a rhombus.
Answer:
LMNO is a rhombus
Step-by-step explanation:
btw i love ur pfp! BLM
A diesel train traveled to the repair yards and
back. It took two hours longer to go there than
it did to come back. The average speed on the
trip there was 70 km/h. The average speed on
the way back was 80 km/h. How many hours
did the trip there take?
A) 15 hours
C) 25 hours
B) 16 hours
D) 10 hours
Answer:
B. 16 hrs
Step-by-step explanation:
Distance = rate × time
The best way to do this is to make a table with the info. We are concerned with the trip There and the Return trip. Set it up accordingly:
d = r × t
There
Return
The train made a trip from A to B and then back to A again, so the distances are both the same. We don't know what the distance is, but it doesn't matter. Just go with it for now. It'll be important later.
d = r × t
There d
Return d
We are also told the rates. There is 70 km/hr and return is 80 km/hr
d = r × t
There d = 70
Return d = 80
All that's left is the time column now. We don't know how long it took to get there or back, but if it took 2 hours longer to get There than on the Return, the Return trip took t and the There trip took t + 2:
d = r × t
There d = 70 × t+2
Return d = 80 × t
The distances, remember, are the same for both trips, so that means that by the transitive property of equality, their equations can be set equal to each other:
70(t + 2) = 80t
70t + 140 = 80t
140 = 10t
14 = t
That t represents the Return trip's time. Add 2 hours to it since the There trip's time is t+2. So 14 + 2 = 16.
B. 16 hours