PRACTICE QUESTIONS CLASSROOM WING

The time period after which interest is added each time to form a new principal is called _____.

Ramu lent a part of $₹3000$ at $2\%$ per annum at S.I. and the remaining part at $3\%$ per annum at S.I. At the end of $3$ years he received an amount of $₹3240$. How much did he lend at $3\%$ ?

The simple interest on$₹1800$  at $R\%$ per annum for $2$ years is equal to the simple interest on $₹4800$ at $15\%$ per annum for $1$ year. Find the simple interest (in $₹$) on $₹2400$  for $3$ years at $R\%$ per annum.

Given that carbon$-14\left(C_{14}\right)$ decays at a constant rate in such a way that it is reduced to $25\%$ in $1244$ years. Find the age of a tree in which the carbon is only $6.25\%$ of the original.

Raju borrowed $₹3500$ from Giri at $10\%$ per annum, under simple interest. After $2$ years when Raju wanted to clear the debt, Giri insisted him to pay the amount at compound interest. What is the difference in the amounts between the two?

A person borrowed a sum of $₹9000$ at a rate of $10\%$ per annum interest compounded annually. He repaid an amount of $₹1900$ at the end of the first year. Find the amount that he has to pay at the end of the next two years in order to repay the rest of the loan completely in a single instalment.​

A certain sum was deposited in a bank at $6\%$ per annum at simple interest for $3$ years. Had it been deposited at a rate of interest $2\%$ per annum more, the interest received would have been $₹750$ more. Find the sum.

A sum was split into three parts. The first part was lent at $10\%$ per annum for $4$ years. The second part was lent at $20\%$ per annum for $6$ years. The third part was lent at $30\%$ per annum for $5$ years. Each part was lent at simple interest and the same amount of simple interest was realised from each. Find the ratio of the first, second and third parts.