Aptitude Day 329

Problems on Percentage:

1. When the price of a product was decreased by 20%, the number sold increased by 40%. What was the effect of the total revenue?

Solution:

                 Total revenue = 100*100 = 10,000.

                New revenue = 80*140 = 11,200.

               Increase in revenue = (11200-10000)/10000 * 100

                                               = 12%.

2. During 1 year, the population of a town increased by 4% and during the next year, the population decreased by 4%. If the total population is 2496 at the end of the 2^nd year, then what was the population size in the beginning of the 1^st year?

Solution:

                  2496/[(1+4/100)(1-4/100)] = 2496/[(104/100)(96/100)]

                                                              = 2500.