At what rate of simple interest per annum will a sum double itself in 8 years?
Answer & explanation
Correct answer: option 1
Let principal = 1
ATQ,
Amount = 2 × 1 = 2
So, S.I. = 1
Now,
S.I. = \(\frac{P\;R\;T}{100}\)
1 = \(\frac{1\;R\;8}{100}\)
R = \(\frac{100}{8}\) = 12.5 %