1. To calculate percentage decrease:
First: look for the difference (decrease) between the two numbers you are equating.Decrease = 120 – 87= 33
Then: divide the decrease by the original number and multiply the answer by 100.% Decrease = 33 ÷ 120 × 100= 0.275 x 100= 27.5% or 28%
2. We have a decrease of 33 which is the amount of change.