Question : The simple interest on a certain sum for 3 years at 14% p.a. is INR 4,200 less than the simple interest on the same sum for 5 years at the same rate. Find the sum.

Question : A certain amount is lent at $x$% p.a. simple interest for 3 years. Instead, if the amount was lent at $3x$% p.a. simple interest for $y$ more years, the simple interest would have been seven times the earlier interest. What is the value of $y?$

Question : Money was lent on simple interest. After 12 years, its simple interest becomes $\frac{3}{5}$ of the money. Find the rate of interest.

Question : The simple interest on Rs. 800 for 6 years at 5.5% per annum is equal to the simple interest on Rs. 600 at 4% per annum for a certain period. The period is:

Question : A sum of Rs. 5,000 is divided into two parts such that the simple interest on the first part for $4 \frac{1}{5}$ years at $6 \frac{2}{3} \%$ p.a. is double the simple interest on the second part for $2 \frac{3}{4}$ years at 4% p.a. The ratio of the second part to the first