कितने समय मे रुपए 2000 , 10 % वार्षिक चक्रवृद्धि ब्याज की दर रुपए 2 ,420 होगी |

Options

A. 3 years
B. `2(1)/(2)"years"`
C. 2 years
D. `1(1)/(2) "years"`

Answer

c

Explanation

(c) Principal = Rs. 2000
Amount = Rs. 24200
Rate % = 10%
By using formula
`2420 = 2000 (1 +(10)/(100))^(n)`
`(2420)/(2000) = (1 + (1)/(10))^(n)`
` (121)/(100)= ((11)/(10))^(n) `
`((11)/(10))^(2)= ((11)/(10))^(n)`
` rArr n = 2 years`
Hence, Required time (‌अभीस्ट समय) = 2 years`
Alternate
Note : In such type of save your valuable time follow the given below method
(अब 2 वर्ष के बाद मूलधन तथा मिश्रधन बराबर अनुपात मे होगा)