Selina solutions concise mathematica class 7 icse Solutions for Chapter 10 simple interest

Q1) Find the S.I. and amount on :

(i) Rs. 150 for 4 years at 5% per year.

(ii) Rs. 350 for 3\frac{1}{2} years at 8% p.a.

(iii) Rs. 620 for 4 months at 8 p. per rupee per month.

(iv) Rs. 3,380 for 30 months at 4\frac{1}{2} % p.a.

(v) 600 from July 12 to Dec. 5 at 10% p.a.

(vi) Rs. 850 from 10th March to 3rd August at 2\frac{1}{2}% p.a.

(vii) Rs. 225 for 3 years 9 months at 16% p.a.

Q2) On what sum of money does the S.I. for 10 years at 5% become Rs. 1,600?

Q3) Find the time in which Rs. 2,000 will amount to Rs. 2,330 at 11% p.a.?

Q4) In what time will a sum of money double itself at 8% p.a?

Q5) In how many years will be ₹870 amount to ₹1,044, the rate of interest being 2\frac{1}{2}\% p.a?

Q6) Find the rate percent if the S.I. on ₹275 is 2 years is ₹22.

Q7) Find the sum which will amount to ₹700 in 5 years at 8% rate p.a.

Q8) What is the rate of interest if ₹3,750 amounts to ₹4,650 in 4 years?

Q9) In 4 years, ₹6,000 amount to ₹8,000. In what time will ₹525 amount to ₹700 at the same rate?

Q10) The interest on a sum of money at the end of 2\frac{1}{2}\ years\ is\ \frac{4}{5} of the sum. What is the rate percent?

Q11) What sum of money lent out at 5% for 3 years will produce the same interest as Rs. 900 lent out at 4% for 5 years?

Q12) A sum of Rs. 1,780 become Rs. 2,136 in 4 years,

Find :

(i) the rate of interest.

(ii) the sum that will become Rs. 810 in 7 years at the same rate of interest?

Q13) A sum amounts to Rs. 2,652 in 6 years at 5% p.a. simple interest.

Find :

(i) the sum

(ii) the time in which the same sum will double itself at the same rate of interest.

Q14) P and Q invest Rs. 36,000 and Rs. 25,000 respectively at the same rate of interest per year. If at the end of 4 years, P gets Rs. 3,080 more interest than Q; find the rate of interest.

Q15) A sum of money is lent for 5 years at R% simple interest per annum. If the interest earned be one-fourth of the money lent, find the value of R.

Q16) The simple interest earned on a certain sum in 5 years is 30% of the sum. Find the rate of interest.