Question

on what principal will the compound interest for 3 years at 5% per annum compound annually is rs. 63.05?

Answer 1

SOLUTION:
Given:
Time(n) = 3 years, Rate(R) = 5% & Compound Interest = ₹ 63.05
Let the principal be ₹ P.
Compound Interest = P{(1 + R/100)ⁿ – 1}
63.05 = P{(1 + 5/100)³ -1}
63.05 = P {(1 + 1/20)³ -1}
63.05 = P {(21/20)³- 1}
63.05 = P{21 x 21 x 21/20 x 20 x 20 -1}
63.05 = P{9261/8000 -1}
63.05 = P (9261 - 8000)/8000
63.05 = 1261 P/8000
P = 63.05 x 8000/1261
P = 6305 x 80/1261
P = 504400/1261
P = ₹ 400
Hence, the principal is ₹ 400.

HOPE THIS WILL HELP YOU...

Answer 2

Given :

Time=n=3 yrs

Rate =r=5%
compound interest=₹63.05

Let P be the principal amount.

Formula to be used :
C.I = p[1 +R/100]ⁿ -1]

63.05=P[1+5/100]³ -1]

63.05=P[1+1/20]³-1]

63.05=P[21/20]³ -1 ]

63.05=P[21x21x21/20x20x20]-1]

63.05=P[9261/8000 -1]

63.05=P[9261-8000/8000]

63.05=P[1261/8000]

P=63.05x8000/1261

=6305x80/1261

=504400/1261

P=₹400