Question

Find the principal if the interest compounded at the rate of 10% per annum for two years is Rs. 420 ?
A) Rs. 2000
B) Rs. 2100
C) Rs. 1900
D) Rs. 2150

Answer 1

Find the principal if the interest compounded at the rate of 10% per annum for two years is Rs. 420 ?
A) Rs. 2000
B) Rs. 2100
C) Rs. 1900
D) Rs. 2150

Given, 
Compound rate, R = 10% per annum
Time = 2 years
C.I = Rs. 420
Let P be the required principal.
A = (P+C.I)
Amount, A = P1 + r100n

(P+C.I) = P1 + 101002

(P+420) = P[11/10][11/10]

P-1.21P = -420

0.21P = 420

Hence, P = 420/0.21 = Rs. 2000