Sum

If one invests Rs. 10,000 in a bank at a rate of interest 8% per annum, how long does it take to double the money by compound interest? [(1.08)^{5} = 1.47]

Advertisement Remove all ads

#### Solution

Amount invested = Rs. 10000

Interest rate = `8/100` = 0.08

amount after 1^{st} year = 10000 (1 + 0.08)

= 10000 (1.08)

Value of the amount after n years

= 10000 (1.08)^{n}

= 20000

∴ (1.08)^{n} = 2

(1.08)^{5} = 1.47 ...[Given]

∴ n = 10 year. (approximately)

Concept: Geometric Progression (G. P.)

Is there an error in this question or solution?

Advertisement Remove all ads

#### APPEARS IN

Advertisement Remove all ads

Advertisement Remove all ads