Aptitude Day 314

Answers of Day 313: 1. 8320.

                                    2. 1622.40.

Problems on Compound Interest:

1. A man saves 400 at the end of each year and leads the money at 10% C.I. How much will it become at the end of 2 years?

Solution:

                    Amount = 400(1 + 10/100)² - 400(1 + 10/100)¹

                                         = 400(1 + 10/100) [(1 + 10/100)+1]

                                  = 400*110/100[110/100 + 1]

                                  = 440(210/100)

                                  = 924.

2. A bank offers 10% C.I. calculated on a half-yearly basis. A customer deposits 3200 each on 1^st January and 1^st July of a year. At the end of the year, the amount he would have gained by way of interest is:

Solution:

                 Amount = 3200(1 + 10/2*100)²⁽¹⁾ + 3200(1 + 10/2*100)^2(1/2)   

                               = 13948.2.

  

                C.I. = 13948.4-(3200+3200) 

                       = 7548.2.