Question

A sum of 16,000, invested at simple interest,
amounts to *22,400 in 4 years at a certain
rate of interest. If the same sum of money is
invested for 2 years at the same rate of
interest, compounded p.a., find the compound
interest earned.​

Answer 1

answer

Amount at the end of 18 months 16000+2522=18522

Now, we know that for CI

A=P(1+nr)nt

where P=16000t=18 months=23 years 

            n=2 (as it is compounded half yearly)

            r= rate of interest

            A= Amount

So, 18522=16000(1+2r)23∗2⇒1600018522=(1+2r)3⇒10.5=1+2r⇒r=19

So, Rate of interest is 1

Step-by-step explanation:

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