#### ₹ 16000 invested at 10% p.a., compounded semi-annually, amounts to ₹ 18522, find the time period of investment.

**Solution:**

It is given that

Principal (P) = ₹ 16000

Amount (A) = ₹ 18522

Rate = 10% p.a. or 5% semi-annually

Consider period = n half years

We know that

A/P = (1 + r/100)^{n}

Substituting the values

18522/16000 = (1 + 5/100)^{n}

By further calculation

9261/8000 = (21/20)^{n}

So we get

(21/20)^{3} = (21/20)^{n}

n = 3 half years

Here

Time = 3/2 = 1 ½ years

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