Susie scored 85, 84,and 78 on three of the four math tests. if her average score for the four tests was 86. what was her score on the fourth test?

Answer:

$825 dollars

Step-by-step explanation:

is the answer i belive hope this helps

1/10 of 400 = 40

1/4 of 40 = 10

1/2 of 10 = 5

the number is 5

There is a solution. Starting from C−1(A+X)B−1=In C−1(A+X)B−1=In, multiply both of the sides of the equation, by C and multiply both sides of the equation by B.

In other terms, this is the solution:

Given: C^(-1)(A + X)B^(-1) = In

= CC^(-1)(A + X)B^(-1)B = CInB

= In(A + X)In = CB

= AInIn + XInIn = CB


= A + X = CB


X = CB – A

The final answer Is X = CB – A

s =1/2(u+v)t

u = 16, v=16, t=90

s = 1/2(16+16)90

s = 1/2(36)90

s = 16*90

s = 1440

Answer:

B. [tex]8\sqrt2+2\sqrt{10}[/tex] units

Step-by-step explanation:

We are given that a parallelogram PQRS in which point P(-2,5), Q(2,1),R(1,-2) and S(-3,2).

We have to find the perimeter of parallelogram PQRS.

Distance formula : [tex]\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]

Using the formula

[tex]SR=\sqrt{(1+3)^2+(-2-2)^2}=4\sqrt2[/tex]units

[tex]QR=\sqrt{(1-2)^2+(-2-1)^2}=\sqrt{10} units[/tex]

Now, the perimeter of parallelogram =2(SR+QR)

The perimeter of parallelogram =[tex]2(4\sqrt2+\sqrt{10})=8\sqrt2+2\sqrt{10} units[/tex]

Answer:B. [tex]8\sqrt2+2\sqrt{10}[/tex] units

Answer:

It would be 3

Step-by-step explanation:

The type of rice which is most expensive is [tex]\boxed{\text{\bf type B}}[/tex].

Further details:

It is given that the rice seller mixes three types of rice and the total number of mixture is three.

The first mixture consists [tex]1\text{ kg}[/tex] rice of type [tex]\text{A}[/tex], [tex]2\text{ kg}[/tex] rice of type [tex]\text{B}[/tex] and [tex]4\text{ kg}[/tex] rice of type [tex]\text{C}[/tex].

The selling price of the first mixture is [tex]19500[/tex].

In equation form it can be written as follows:

[tex]\boxed{\text{A}+2\text{B}+4\text{C}=19500}[/tex]      .......(1)

The second mixture consists [tex]2\text{ kg}[/tex] rice of type [tex]\text{A}[/tex] and [tex]3\text{ kg}[/tex] rice of type [tex]\text{B}[/tex].

The selling price of the second mixture is [tex]19000[/tex].

In equation form it can be written as follows:

[tex]\boxed{2\text{A}+3\text{B}=19000}[/tex]   ......(2)

The third mixture consists [tex]1\text{ kg}[/tex] rice of type [tex]\text{B}[/tex] and [tex]1\text{ kg}[/tex] rice of type [tex]\text{C}[/tex].

The selling price of the third mixture is [tex]6250[/tex].

In equation form it can be written as follows:

[tex]\boxed{\text{B}+\text{C}=6250}[/tex] ........(3)

Rearrange the equation (3) to obtain the value of [tex]\text{B}[/tex] as follows:

[tex]\text{B}=6250-\text{C}[/tex]            ...........(4)

Substitute this value of [tex]\text{B}[/tex] in equation (2).

[tex]\begin{aligned}2\text{A}+3(6250-\text{C})&=19000\\2A+(3\cdot 6250)-3\text{C}&=19000\\2\text{A}-3\text{C}+18750&=19000\\2\text{A}-3\text{C}&=19000-18750\\2\text{A}-3\text{C}&=250\end{aligned}[/tex]  

Further solve the above equation,

[tex]\text{A}-1.5\text{C}=125[/tex]   ......(5)

Now substitute the value of [tex]\text{B}[/tex] from equation (4) in equation (1) to obtain an equation in the form of [tex]\text{A}[/tex] and [tex]\text{C}[/tex] as follows,

[tex]\begin{aligned}\text{A}+2(6250-\text{C})+4\text{C}&=19500\\ \text{A}+(2\cdot 6250)-2\text{C}+4\text{C}&=19500\\ \text{A}+12500+2\text{C}&=19500\\ \tex{A}+2\text{C}&=19500-12500\end{aligned}[/tex]

Further the above equation can be simplifies as follows,

[tex]\text{A}+2\text{C}=7000[/tex]            .......(6)

Subtract the equation (4) from (5) to obtain the value of [tex]\text{A}[/tex] and [tex]\text{C}[/tex].  

[tex]\begin{aligned}\text{A}+2\text{C}-\text{A}+1.5\text{C}&=7000-125\\3.5\text{C}&=6875\\ \text{C}&=1964.3\end{aligned}[/tex]

Substitute this value of [tex]\text{C}[/tex] in equation (5) to obtain the value of [tex]\text{A}[/tex] as follows,

[tex]\begin{aligned}\text{A}+(2\cdot 1964.3)&=7000\\ \text{A}&=7000-3928.6\\ \text{A}&=3071.4\end{aligned}[/tex]

Again substitute [tex]\text{C}=1964.3[/tex] in equation (4) to obtain the value of [tex]\text{B}[/tex].

[tex]\begin{aligned}\text{B}&=6250-1964.3\\&=4285.7\end{aligned}[/tex]  

Therefore, the most expensive type of rice is [tex]\boxed{\text{\bf type B}}[/tex].

Learn more:

1.  Problem on percentage in a survey: https://brainly.com/question/3724002

2. Problem on unit conversion factor: https://brainly.com/question/5009365

3. Problem on to find the value in pounds: https://brainly.com/question/4837736

Answer details:

Grade: Middle School

Subject: Mathematics

Chapter: Mixtures

Keywords:  Rice seller, mixture, sold, expensive, type A, type B, type C, simplification, consist, 19500, 1 kg,addition, substitution, multiplication.

Final answer:

To solve the literal equation for y in the given equation a=9y-3yx, we can rearrange the terms and isolate y on one side. The solution for y is (a - 9y) / (-3x).

Explanation:

To solve the literal equation for y, we need to isolate y on one side of the equation.

Given the equation a = 9y - 3yx, we can start by rearranging the terms.

Subtract 9y from both sides:

a - 9y = -3yx

Divide both sides by -3x:

(a - 9y) / (-3x) = y

So, the solution for y is (a - 9y) / (-3x).

Final answer:

To solve the given literal equation for y, factor out y and then divide by (9 - 3x) to obtain the equation y = a / (9 - 3x), which allows y to be expressed in terms of a and x.

Explanation:

To solve the literal equation for y given as a = 9y - 3yx, we want to isolate y on one side of the equation. To do this, we first factor out y from the terms on the right side of the equation:

a = y(9 - 3x)

Next, we divide both sides of the equation by (9 - 3x) to get y by itself:

y = a / (9 - 3x)

This equation represents the value of y in terms of a and x. In the context of a linear equation, such as y = 9 + 3x, the number 9 is the y-intercept (denoted as the b term), and the number 3 is the slope (denoted as the m term).

Answer:

Darrel is 20 ft above sea level.

Step-by-step explanation:

We have been given that Darrel is currently 20 feet below sea level.

This means that Darrel's elevation would be [tex]-20[/tex] ft.

The opposite of Darrel's elevation would be negative of [tex]-20[/tex] ft.

[tex]-(-20)=20[/tex]

Since opposite of Darrel's current elevation is positive 20 ft, therefore, Darrel is 20 ft above sea level.

Answer: –5x – x2

Step-by-step explanation:

edge.