Contents

## Selina Publishers Concise Mathematics Class 7 ICSE Solutions Chapter 10 Simple Interest

**Selina Publishers Concise Mathematics Class 7 ICSE Solutions Chapter 10 Simple Interest**

### Simple Interest Exercise 10 – Selina Concise Mathematics Class 7 ICSE Solutions

**Question 1.**

**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.
**

**Solution:**

**Question 2.**

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

**Solution:**

**Question 3.**

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

**Solution:**

**Question 4.**

**In what time will a sum of money double it self at 8% p.a ?
**

**Solution:**

**Question 5.**

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

**Solution:**

**Question 6.**

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

**Solution:**

**Question 7.**

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

**Solution:**

**Question 8.**

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

**Solution:**

**Question 9.**

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

**Solution:**

**Question 10.**

**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 ?
**

**Solution:**

**Question 11.**

**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 ?
**

**Solution:**

**Question 12.**

**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 ?
**

**Solution:**

**Question 13.**

**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.
**

**Solution:**

**Question 14.**

**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.
**

**Solution:**

**Question 15.**

**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.
**

**Solution:**

**Question 16.**

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

**Solution:**