Question

Sam wants to earn at least a B in Math. He earned the following scores on tests so far: 82%, 70%, 72%, and 80%.

Which inequality below can be used to solve and determine what Sam needs to earn on the final exam in order to have at least a B-average in the class?

Answer 1

Sam has to get at least a 96 in order to pass the class with a B.

Explanation:

To find this you use mean in this format:

Test Scores + x (Exam Grade Needed) / # of Tests ≥ 80 (Which Is a B)

Substitute:

82 + 70 + 72 + 80 + x / 5 ≥ 80

Add:

304 + x / 5 ≥ 80

Get Rid of the Denominator (Multiply Both Sides By 5):

(5) 304 + x / 5 ≥ 80 (5)

Multiply:

304 + x ≥ 400

Isolate x (Subtract 304 From Both Sides):

x ≥ 96

This means that Sam has to get at least (Greater than or equal to) a 96 in order to pass with a B average.