Find the rate percent per annum, if Rs. 2000 amount to Rs. 2315.25 in

1.	Find the rate percent per annum, if Rs. 2000 amount to Rs. 2315.25 in a year and a half, interest being compounded six monthly.
Answer» Given details are, Principal = Rs 2000 Amount = Rs 2315.25 Time = 1 ½ years = 3/2 years Let rate be = R % per annum By using the formula, A = P (1 + R/100)ⁿ 2315.25 = 2000 (1 + R/100)^3/2 (1 + R/100)^3/2 = 2315.25/2000 (1 + R/100)^3/2 = (1.1576) (1 + R/100) = 1.1025 R/100 = 1.1025 – 1 = 0.1025 × 100 = 10.25 ∴ Required Rate is 10.25% per annum.

Find the rate percent per annum, if Rs. 2000 amount to Rs. 2315.25 in a year and a half, interest being compounded six monthly.

Answer»

Given details are,

Principal = Rs 2000

Amount = Rs 2315.25

Time = 1 ½ years = 3/2 years

Let rate be = R % per annum

By using the formula,

A = P (1 + R/100)ⁿ

2315.25 = 2000 (1 + R/100)^3/2

(1 + R/100)^3/2 = 2315.25/2000

(1 + R/100)^3/2 = (1.1576)

(1 + R/100) = 1.1025

R/100 = 1.1025 – 1

= 0.1025 × 100

= 10.25

∴ Required Rate is 10.25% per annum.