Question

A sum of money at simple interest triples itself in 10 years.in how much time will it be five time of itself?

Answer 1

Answer:

p×r×t/100 = SI

p+SI = 3p (in 10 yrs)

SI = 2p

p×r×10/100 = 2p

p×r = 20p

r = 20

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p+SI = 5p

SI = 4p

p×r×t/100 = 4p

p×20×t/100 = 4p

p×t/5 = 4p

p×t = 20p

t = 20years