Tricky Questions Percentage

x

Option: D

Explanation

Consider the original salary be Rs.100

if the salary was reduced by 10%, his new salary will be Rs.90

Increase on 90 = 10%

so, increase on 100 = ((10/90) * 100)% = 100/9%)

Ans = 100/9%

x

Option: A

Explanation

Consider the price of the product be Rs.100

consider the original sale be 100 pieces

then, total revenue = Rs.(100 * 100) = Rs.10000

if the price of product was decreased by 10% and number of pieces be increased by 30%

then, new total revenue = Rs.(90 * 130) = Rs.11700

increase in revenue = ((11700/10000) * 100)% = 17%

Ans = 17%

x

Option: B

Explanation

In one year the population is increased by 5%

In next year the population is decreased by 5%

at the end of second year the population is 9975

then the population in the beginning of the first year is given by,

9975/[(1 + (5/100)) * (1 - (5/100))]

(9975 * (20/21) * (20/19)) = 10000

Ans = 10000

x

Option: C

Explanation

amount of salt in 30 kg solution = (2/100) * 30kg = 0.6kg

consider x kg of pure salt be added

then, (0.6 + x)/(30 + x) = 10/100

60 + 100x = 300 + 10x

90x = 240

x = 8/3

Ans = 8/3