The document RD Sharma Solutions (Part - 1) - Ex-13.1, Simple Interest, Class 7, Math Class 7 Notes | EduRev is a part of the Class 7 Course RD Sharma Solutions for Class 7 Mathematics.

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**Find the simple interest, when: (i) Principal = Rs 2000, Rate of Interest = 5% per annum and Time = 5 years. (ii) Principal = Rs 500, Rate of Interest = 12.5% per annum and Time = 4 years. (iii) Principal = Rs 4500, Rate of Interest = 4% per annum and Time = months. (iv) Principal = Rs 12000, Rate of Interest = 18% per annum and Time = 4 months. (v) Principal = Rs 1000, Rate of Interest = 10% per annum and Time = 73 days.**

(i) Principal (*P*) = Rs 2000

Rate of interest (*R*) = 5% p.a.

Time (*T*) = 5 years

Simple interest =

(ii) Principal (*P*) = Rs 500

Rate of interest (*R*) = 12.5% p.a.

Time (*T*) = 4 years

Simple interest =

(iii) Principal (*P*) = Rs 4500

Rate of interest (*R*) = 4% p.a.

Time (*T*) = 6 months

Simple interest =

(iv) Principal (*P*) = Rs 12000

Rate of interest (*R*) = 18% p.a.

Time (T) = 4 months (1 year = 12 months)

Simple interest =

(v) Principal (*P*) = Rs 1000

Rate of interest (*R*) = 10% p.a.

Time (T) = 73 days =

Simple interest =

**Find the interest on Rs 500 for a period of 4 years at the rate of 8% per annum. Also, find the amount to be paid at the end of the period.**

Principal amount (*P*) = Rs 500

Time period (*T*) = 4 years

Rate of interest (*R*) = 8% p.a.

Interest =

Total amount paid = Principal amount + Interest = Rs 500 + 160

= Rs 660

**A sum of Rs 400 is lent at the rate of 5% per annum. Find the interest at the end of 2 years.**

Principal amount (*P*) = Rs 400

Time period (*T*) = 2 years

Rate of interest (*R*) = 5% p.a.

Interest paid after 2 years=

**A sum of Rs 400 is lent for 3 years at the rate of 6% per annum. Find the interest.**

Principal amount (*P*) = Rs 400

Time period (*T*) = 3 years

Rate of interest (*R*) = 6% p.a.

Interest after 3 years =

**A person deposits Rs 25000 in a firm who pays an interest at the rate of 20% per annum. Calculate the income he gets from it annually.**

Principal amount (*P*) = Rs 25000

Time period (*T*) = 1 year

Rate of interest (*R*) = 20% p.a.

Annual interest =

**A man borrowed Rs 8000 from a bank at 8% per annum. Find the amount he has to pay after 412412years.**

Principal amount (*P*) = Rs 8000

Time period (*T*) =

Rate of interest (*R*) = 8% p.a.

Interest =

Total amount paid after = Principal amount + Interest = Rs 8000 + Rs 2880 = Rs 10880

**Rakesh lent out Rs 8000 for 5 years at 15% per annum and borrowed Rs 6000 for 3 years at 12% per annum. How much did he gain or lose?**

Principal amount lent out by Rakesh (*P*) = Rs 8000

Time period (*T*) = 5 years

Rate of interest (*R*) = 15% p.a.

Interest =

Principal amount borrowed by Rakesh (*P*) = Rs 6000

Time period (*T*) = 3 years

Rate of interest (*R*) = 12% p.a.

Interest =

Amount gained by Rakesh = Rs 6000 âˆ’ Rs 2160 = Rs 3840

**Anita deposits Rs 1000 in a savings bank account. The bank pays interest at the rate of 5% per annum. What amount can Anita get after one year?**

Principal amount (*P*) = Rs 1000

Time period (*T*) = 1 year

Rate of interest (*R*) = 5% p.a.

Interest =

Total amount paid after 1 year = Principal amount + Interest = Rs 1000 + Rs 50 = Rs 1050

**Nalini borrowed Rs 550 from her friend at 8% per annum. She returned the amount after 6 months. How much did she pay?**

Principal amount (*P*) = Rs 550

Time period (*T*) = 6 months = (1 year = 12 months)

Interest =

Total amount paid after 6 months = Principal amount + Interest = Rs 550 + Rs 22 = Rs 572

**Rohit borowed Rs 600000 from a bank at 9% per annum for 2 years. He lent this sum of money to Rohan at 10% per annum for 2 years. How much did Rohit earn from this transaction?**

Principal amount lent out by Rohit (P) = Rs. 60000

Time period (T) = 2 years

Rate of interest (R) = 10% p.a.

Interest =

Principal amount borrowed by Rohit from the bank (P) = Rs. 60000

Time period (T) = 2 years

Rate of interest (R) = 9% p.a.

Interest =

Amount gained by Rohit = Rs. 12000 - 10800 = Rs. 1200

**Romesh borrowed Rs 2000 at 2% per annum and Rs 1000 at 5% per annum. He cleared his debt after 2 years by giving Rs 2800 and a watch. What is the cost of the watch?**

Principal amount borrowed by Romesh (P) = Rs. 2000

Time period (T) = 2 years

Rate of interest (R) = 2% p.a.

Interest =

Principal amount borrowed by Romesh (P) = Rs. 1000

Time period (T) = 2 years

Rate of interest (R) = 5% p.a.

Interest =

Total amount that he will have to return = Rs. 2000 + 1000 + 80 + 100 = Rs. 3180

Amount repaid = Rs. 2800

Value of the watch = Rs. 3180 - 2800 = Rs. 380