Tip:A–D to answerE for explanationV for videoS to reveal answer
If a number is increased by 30% and then decreased by 20%, what is the net change?
- A.
4% increase
(Correct Answer) - B.
6% increase
- C.
8% Increase
- D.
6% decrease
Correct Answer: 4% increase
Explanation
Method 1: Formula
Take x=+30 and y=−20:
Net Change=(30−20+10030×(−20))%
Method 2: Ratio/Assumed Value Let the number be 100.
-
100+30%130
-
130−20%130−26=104
Net change =104−100=4%
Correct Option: B) 4% increase
Explanation
Method 1: Formula
Take x=+30 and y=−20:
Net Change=(30−20+10030×(−20))%
Method 2: Ratio/Assumed Value Let the number be 100.
-
100+30%130
-
130−20%130−26=104
Net change =104−100=4%
Correct Option: B) 4% increase
