what amount of money will become taka 2050 as profit principal in 4 years,at the same rate of profit at which some principal becomes double as profit principal in 6 years?

Question

Taka is Bangladeshi currency.

Answer 1

I interpret this question as:

What principal amount of money will gain taka 2050 interest in 4 years at the same interest rate as the same amount of money would be doubled in 6 years?

The interest gained in 6 years causes the principal amount to be doubled, so interest=principal, which we'll call P. Call the rate R and assume simple interest.

Interest=PTR where T=time. So 4PR=2050, the amount of interest earned in 4 years.

6PR=P, the amount of interest earned in 6 years, which added to P would double it.

So if 6PR=P, then R=1/6. 4PR=4P/6=2050, and P=3*2050/2=3075.

So the principal amount is taka 3075.

ALTERNATIVE INTERPRETATION AND SOLUTION

Taka 2050 may be interpreted as the total amount (principal + interest earned over 4 years).

So P+4PR=2050. P+6PR=2P, 6PR=P, R=1/6 as before.

P+4PR=P+2P/3=2050, 5P/3=2050, P=3*2050/5=3*410=1230. The principal is taka 1230.