A man gave $50 \%$ of his savings of ₹ $84,100$ to his wife and divided the remaining sum among his two sons $A$ and $B$ of $15$ and $13$ years of age respectively. He divided it in such a way that each of his sons, when they attain the age of $18$ years, would receive the same amount at $5 \%$ compound interest per annum. The share of $B$ was (In ₹)

A certain sum of money invested at compound interest becomes $1.44$ times of itself in $2$ years. If twice this sum were lent at simple interest, in how many years would it double itself?

What will be the compound interest (In ₹) on a sum of ₹ $50000$ after $4$ years at the rate of $10 \%$ per annum?

The sum for $2$ years gives a compound interest of ₹ $3225$ at the rate of $15 \%$ per annum the amount is (In ₹) 

What is $C.I.$ (In $Rs.$) on $Rs. 7500$ for $4$ years if the rate of interest is $10 \%$ p.a. for the first $2$ year and $20 \%$ $p.a.$ for the next $2$ year?

The principal that amounts to ₹ $4913$ in $3$ years at $6 \frac{1}{4} \%$ per annum compound interest compounded annually (In ₹) is.