Question

*I ALREADY GOT THE ANSWER JUST WANT TO MAKE SURE IM CORRECT THANKS*

devonte's scores on his first four spanish tests are 92,85,90,and 92. what test score must devonte earn on the fifth test so that the mean will be exactly 90?

*i think the answer is 91*

Answer 1

So to get the mean, you need to work out the sum of the values and divide it by the number of values there are.

This means you should do:

(Let x represent the fifth score)

(92 + 85 + 90 + 92 + x) / 5 = 90
(92 + 85 + 90 + 92 + x) = 450
359 + x = 450
x = 450 - 359
x = 91

So the answer is 91 and you are correct :)

Answer 2

Note that the fifth test = x

There are 5 tests, and the mean will be 90

" (92 + 85 + 90 + 92 + x)/5 = 90 " is your equation

Simplify

(359 + x)/5 = 90

Isolate the x. Note the equal sign. What you do to one side, you do to the other. Do the opposite of PEMDAS.

(359 + x)/5 (5) = 90(5)

359 + x = 450

Isolate the x. subtract 359 from both sides

x + 359 (-359) = 450 (-359)

x = 450 - 359

x = 91

Answer: 91

hope this helps