Question

The price of a gallon of unleaded gas was $2.85 yesterday. Today, the price fell to $2.79. Find the percentage decrease. Round your answer to the nearest tenth of a percent.

Also this is for twenty points.

Answer 1

Explanation:

2.85-2.79 is 0.06

0.06/2.85 X 100 is 2.1% decrease

Answer 2

Percentage rounded to nearest tenth:

2.1%

Explanation:

Let P represent the decrease percentage

2.85 - 2.85×(P÷100) = 2.79

then

2.85×(1 - (P÷100)) = 2.79

then

2.85×(100 - P)÷100 = 2.79

then

100 - P = (2.79×100)÷2.85 = 97.894736842105

then

P = 100-97.894736842105 = 2.105263157895