Question

a number is first increased by 20% and then decreased by 15%. find the net increase or decrease percent

Answer 1

Let the number to be 100

Number Increase by 20%

100 + 20% of 100

= 100 + ( (20/100)×100 )

= 100 + 20 = 120


The resulting number decreased by its 15%

= 120- (15/100×120)

= 120 - 18

= 102

Now, net increase =102-100 = 2

Increase % = (net increase / Original number × 100) %


= ( 2 / 100 ×100 )%

= 2%.

Hence, the increase percent = 2%

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Hope this will help you...

Answer 2

Solution :-

Let the required number be 100

Now, according to the question.

The number is first increased by 20 %

⇒ 100 + 20 % of 100

⇒ 100 + [(20*100)/100]

⇒ 100 + 20

⇒ 120

Then, it is decreased by 15 %

⇒ 120 - (15 % of 120)

⇒ 120 - [(15*120)/100]

⇒ 120 - 18

= 102

Net increase = 102 - 100

= 2

Percent increase = (Change in number*100)/100

⇒ (2*100)/100 

= 2 %

Hence, the increase percent is 2 %.

Answer.