penny made a 74% on her first test. what must she get on her next test to have an average of at least 80%

Question

penny made a 74% on her first test. what must she get on her next test to have an average of at least 80% ( 100 points per test)

Answer 1

The average of her scores is equal to:

((test one score) + (test two score)) / 2

In variable form:

(x + y)/2

Where x is Penny's percentage score on the first test, and y is her percentage score on the second test.

So x = 74:

(74 + y) / 2 = 80 (set the formula equal to the minimum average score)

Solving for y we get:

74 + y = 160 (multiply both sides by 2)

y = 160 - 74

y = 86

Therefore, Penny must score an 86% or higher on her next test to have an overall average of 80% or more.

Answer 2

An intuitive approach would be to realize that since 74 is 6 points below the required minimum average of 60, the 2nd test must have a score at least 6 points above 80, giving 86.