Question 59
A man gets double the amount in 7 years at a certain rate percent. In how many years, he gets 8 the amount at the same rate?
Solution
Using the formula : $$\frac{N_1-1}{N_2-1}=\frac{T_1}{T_2}$$
Let in $$t$$ years, he gets 8 times the amount.
=> $$\frac{2-1}{8-1}=\frac{7}{t}$$
=> $$\frac{1}{7}=\frac{7}{t}$$
=> $$t=49$$ years
=> Ans - (B)
