# Find the compound interest on rs 2000 at 20% pa for one and half years the interest being compounded half yearly? and quarterly?

2
by ekalavyaachanta
Compounded half yearly:
P = Rs 2,000. r = 20%
n = number of times compounded = 1.50 yrs / 0.50 yrs = 3 times
Sum = P (1+r/100)^n = 2, 000 (1 + 20/100)^3 = Rs 2,000 * 1.2^3
Compound interest = sum - P = Rs 2, 000 (1.2^3 - 1) = Rs 1, 456
compounded quarterly:
n = 1.50 yrs / 0.25 yrs = 6
Sum = Rs 2, 000 ( 1 + 20/100)^6 = Rs 2, 000 * 1.2^6
interest = Rs 3, 971.97
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Sorry. above there is a mistake.. rate of interest is only 10% for 6 months.
Compounded half yearly:
P = Rs 2,000. r = 20% per annum.. r = 10% per half year.
n = number of times compounded = 1.50 yrs / 0.50 yrs = 3 times
Sum = P (1+r/100)^n = 2, 000 (1 + 10/100)^3 = Rs 2,000 * 1.1^3
Compound interest = sum - P = Rs 2, 000 (1.1^3 - 1) = Rs 662
compounded quarterly:
n = 1.50 yrs / 0.25 yrs = 6
Sum = Rs 2, 000 ( 1 + 10/100)^6 = Rs 2, 000 * 1.1^6
compound interest = Rs 1, 543.12
the interests are : Rs 662, and Rs 1, 543.12 respectively.