Question

Find the rate percent per annum, if ₹2000 amounts to  ₹2,315,25 in a year and a half, interest being compounded half-yearly. 

विकल्प

• 11.5%

• 10%

• 5%

• 20%

Answer 1

10%

Explanation:

t → `1 1/2` years = 3 terms

`(1 + "r"/100)^3 = (2315.25)/(2000)`

`(1 + "r"/100)^3 = 9261/8000`

`(1 + "r"/100)^3 = (21/20)^3` 

`1 + "r"/100 = 21/20`

`"r"/100 = 1/20`

r = 5% half yearly

10% yearly