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Heather received grades of 80, 75, and 86 on 3

math 1 tests. What is lowest grade she can
receive on the next test if she wants her average
for the four test to be at least an 82?
Define your variable

User ManOVision
by
3.9k points

1 Answer

3 votes

Answer:

87

Explanation:

We know Heather recieved grades of 80, 75 and 86.

Let's find her average on those 3 tests.

80 + 75 + 86 = 241 Since there are 3 tests we divide by 3.

241/3 = 80.3333 Is her aveerage on the first 3 tests.

She need to average 82 so we can write an equation with t being the score on her 4th test.


(80 + 75 + 86 + t)/(4) = 82


(241 + t)/(4) = 82 Multiply each side by 4

(
(241+t)/(4)) * 4 = 82 * 4 4 on the left will cancel

241 + t = 328 Subtract 241 from each side

241 - 241 + t = 328 - 241

t = 328 - 241

t = 87

Heather must get an 87 to have an average score of 82.

User Alan Kay
by
4.6k points