Question

Find the number of years for which the compound interest of rs. 9000 is rs.1890 at rate of 10 p.c.p.a
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Answer 1

Step-by-step explanation:

It is given that ,

Principal ( P ) = RS 9000

compound interest ( C.I ) = RS 1890

Rate of interest ( R ) = 10% p.a

Let the number of times interest paid = n

Amount ( A ) = P + C.I

A = Rs 9000 + Rs 1890

A = Rs 10890

A = P( 1 + R/100 )ⁿ

10890 = 9000 ( 1 + 10/100 )ⁿ

10890/9000 = ( 1 + 1/10 )ⁿ

121/100 = ( 11/10 )ⁿ

( 11/10 )² = ( 11/10 )ⁿ

2 = n

[ since , if a^m = aⁿ then m = n ]

n = 2

Therefore ,

Number of years interest paid = n = 2