Question

The salary of an employee is first increased by 20% and the again increased by 30%. find percentage increase in his salary from the original salary.

Answer 1

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 2

let the salary be 100
now salary increased by 20 %
new salary = 100 + 100×20/100 =100 + 20 = 120
again new salary increased by 30 %
then , present salary = 120 + 120×30/100 = 120+36 = 156
difference between present salary and original salary = 156-100 =56
percent increased in original salary = 56×100/100 = 56℅