Need help solving a word problem..?

Question

here we go:

Going into the final exam, which will count as two tests, Brooke has test scores of 80,83,71,61, and 95. What score does Brooke need on the final in order to have an average score of 80?


need help coming up with the formula to solve

thank you in advance.

Answer 1

well this is an average quetion so you set it up like one
total of the scores over the numbet of tests equals 80

80
+83
+71
+61
+95
+2x ( cos it os counting as 2) = 390+2x

now you know that (390+2x) / 7 = 80

you are dividing by 7 cos there are 7 tests


now multiply both sides y 7
390+2x = 80*7
390+2x = 560
-390 -390

2x = 170
divide both sides by 2
x= 85

Answer 2

(80 + 83 + 71 + 61 + 95 + 2x) / 7 = 80
(390 + 2x) /7 = 80
2x + 390 = 560
2x = 170
x = 85

if Brooke gets a score of 85 on the final exam (which will count as two tests), Brooke will have an average score or 80.

Answer 3

the number of test that will be taken is (5 + the 2 left to take) =7,
to get an average of 80 the total score will have to be 7x80=560
she already has 390 so the remainder is 170.
However as this test count as two test she will only need to score 170/2 = 85

Answer 4

(80+83+71+61+95 +2x)/7 = 80
(390 +2x)/7 = 80
390 + 2x = 560
2x = 170
x = 85

Answer 5

(80+83+71+61+95+X+X)/7=80

Answer 6

confident you may label the variable x as width and length could be x + 12 make an equation 2x + 2(x+12) = 156 on the grounds which you upload all sides to get perimeter then u sparkling up for x yielding the respond x = 33 = width x + 12 = 40 5 = length

Answer 7

Average X Number (of tests) = Total (of all scores)

or: A x N = T

You can solve from here.