Correct Answer - Option 1 : 23184.525
Given:
An amount under simple interest fetches an interest 6 times of itself in 40 years.
The same rate of interest is applied on an amount of Rs. 71890 for two years under compound interest.
Formula Used:
Amount after n years under compound interest = p × (1 + r/100)n
Compound Interest = p × [1 + (r/100)]n – p [Where p is Principal, r is interest rate, n is time period]
Calculation:
Let the sum be x.
And Interest = 6x
S I = (p × r × t)/100
⇒ 6x = (x × r × 40)/100
⇒ r = 15
For second case,
Interest = Rs. [71890 × (1 + 15/100)2 – 71890] = Rs. [95074.525 – 71890] = Rs. 23184.525
∴ The interest is Rs. 23184.525