**Rd Sharma Solutions Class 7 Chapter 13 Simple Interest**

Welcome to NCTB Solution. Here with this post we are going to help 7th class students for the Solutions of Rd Sharma Class 7 Mathematics, Chapter 13, Simple Interest. Here students can easily find Exercise wise solution for chapter 13, Simple Interest. Students will find proper solutions for Exercise 13.1. Our teachers solved every problem with easily understandable methods so that every students can understand easily. Here all solutions are based on the CBSE latest curriculum.

**Simple Interest Exercise 13.1 Solution**

**Question no – (1) **

**Solution : **

**(i)** According to the question,

Principal = Rs 2000,

Rate of Interest = 5% per annum

Time = 5 years

Simple Interest (S.I.) = ?

We know that,

Simple Interest (S.I.) = (p × r × t/100)

**∴** Simple Interest (S.I.)

= 2000 × 5 × 5/100

= 500 Rs.

Thus Simple Interest will be Rs 500.

**(ii)** As per the question,

Principal = Rs 500

Rate of Interest = 12.5 % per annum

Time = 4 years

Simple Interest (S.I.) = ?

Simple Interest (S.I.) = (P× R × T/100)

**∴** Simple Interest (S.I.)

= 500 × 12.5 × 4/100

= 250 Rs.

Thus Simple Interest will be Rs 250.

**(iii)** In the given question,

Principal = Rs 4500,

Rate of Interest = 4% per annum

Time = 6 month

Simple Interest (S.I.) = ?

We know that,

Simple Interest (S.I.)

= (P × R × T/100)

**∴** Simple Interest (S.I.)

= 4500 × 4 × 1/2/100

= 4500 × 4 × 1/ 2 × 100

= 90 Rs.

Therefore, the Simple Interest will be Rs 90.

**(iv)** From the question we get,

Principal = Rs 12000,

Rate of Interest = 18% per annum

Time = 4 months

Simple Interest (S.I.) = ?

Simple Interest (S.I.)

= (P × R × T/100)

**∴** Simple Interest (S.I.)

= 12000 × 18 × 4/12/100

= 12000 × 18 × 4/12 × 100

= 720 Rs.

Hence, the Simple Interest will be 720 Rs.

**(v)** As per the given question,

Principal = Rs 1000,

Rate of Interest = 10 % per annum

Time = 73 days

Simple Interest (S.I.) = ?

We know that,

Simple Interest (S.I.)

= (P × R × T/100)

**∴** Simple Interest (S.I.)

= 1000 × 10 × (73/365)/100

= 1000 × 10 × 73/365 × 100

= 20 Rs.

Therefore, the Simple Interest will be Rs 20.

**Question no – (2) **

**Solution : **

According to the question,

Principal = Rs 500,

Rate of Interest = 8% per annum

Time = 4 years

Interest = ?

**∴** Interest = 500 × 4 × 8/100

= 160 Rs.

**∴** Amount to paid,

= (500 + 160)

= 660 Rs.

Therefore, the interest is Rs. 160 and amount paid is Rs.660

**Question no – (3) **

**Solution : **

As per the question,

Principal = Rs 400,

Rate of Interest = 5% per annum

Time = 2 years

Interest = ?

**∴** Interest,

= 400 × 2 × 5/100

= 40 Rs.

Therefore, the interest at the end of 2 years is Rs. 40.

**Question no – (4) **

**Solution : **

According to the given question,

Principal = Rs 400,

Rate of Interest = 6% per annum

Time = 3 years

Interest = ?

**∴** Interest,

= 400 × 3 × 6/100

= 72 Rs.

Therefore, the interest will be Rs. 72

**Question no – (5) **

**Solution : **

In the given question,

Principal = Rs 25000,

Rate of Interest = 20% per annum

Time = 1 years

Interest = ?

**∴** Interest,

= 25000 × 20 × 1/100

= 5000 Rs.

Therefore, he will gets 5000 from it annually.

**Question no – (6) **

**Solution : **

In the given question,

Principal = Rs 8000,

Rate of Interest = 8% per annum

Time = 4 1/2 years

Interest = ?

**∴** Interest,

= 8000 × 8 × (4 1/2)/100

= 8000 × 8 × 9/2 × 100

= 2880 Rs.

**∴** Amount has to pay,

= 8000 + 2880

= 10,880 Rs.

**Question no – (7) **

**Solution : **

We know that,

Simple Interest (S.I.) = (P × R × T/100)

**∴** Lent, interest,

= 8000 × 5 × 15/100

= 6000 Rs.

**∴** And for borrow interest,

= 60 × 3 × 12/100

= 2160 Rs.

**∴** He gain,

= (6000 – 2160)

= 3840 Rs.

Therefore, Rakesh will gain Rs. 3840

**Question no – (8) **

**Solution : **

As per the question,

Principal = Rs 1000,

Rate of Interest = 5% per annum

Time = 1 years

Interest = ?

**∴ **Interest,

= 1000 × 5 × 1/100

= 50 Rs.

**∴** Anita will get,

= 100 + 50

= 1050 Rs.

Hence, Anita will get Rs. 1050 after one year.

**Question no – (9) **

**Solution : **

According to the given question,

Principal = Rs 550,

Rate of Interest = 8% per annum

Time = 6 months

Interest = ?

**∴ **Interest,

= 550 × 8 × (1/2) /100

= 550 × 8 × 1/100 × 2

= 22 Rs.

**∴** She had pay,

= 550 + 22

= 572 Rs.

Thus, she had to pay Rs. 572

**Question no – (10) **

**Solution : **

As we know that,

Simple Interest (S.I.) = (P × R × T/100)

**∴** For Borrowing interest,

= 60000 × 9 × 2/100

= 10,800 Rs.

**∴** For lent Interest,

= 60000 × 10 × 2/100

= 12000

**∴** And he earn,

= (12000 – 10800)

= 1200 Rs.

Therefore, Rohit will earn Rs 1200 from this transaction.

**Question no – (11) **

**Solution : **

As we know that,

Simple Interest (S.I.) = (P × R × T/100)

**∴** Interest,

= 2000 × 2 × 2/100

= 80 Rs.

**∴** And also interest

= 1000 × 5 × 2/100

= 100 Rs.

**∴** Total amount,

= 2000 + 80 + 1000 + 80

= 3180 Rs.

Cash paid = 2800

**∴** Cost of the watch,

= (3180 – 2800)

= 380 Rs.

Therefore, the cost of the watch is Rs. 380

**Question no – (12) **

**Solution : **

We know that,

S.I = (P × R × T/100)

**∴** Interest for first,

= 12500 × 3 × 15/100

= 5625

**∴** And interest for rest,

= 2500 × 3 × 18/100

= 1350

**∴** He earn in 3 years,

= 5625 + 1350

= 6975

Therefore, Mr. Garg will earn Rs. 6975 in 3 years.

**Question no – (13) **

**Solution : **

We know that,

S.I = (P × R × T/100)

Interest for one year,

= 2000 × 6 × 1/100

= 120

After withdrew,

Interest,

= 1300 × 6 × 2/100

= 156

Her balance would be,

= 1300 + 120 + 156

= 1576

Hence, Shikha’s balance will be Rs. 1576 after 3 years.

**Question no – (14) **

**Solution : **

As we know that,

Simple Interest (S.I.) = (P × R × T/100)

**∴** Interest,

= 8000 × 18 × 2/100

= 2880 Rs.

**∴** He paid totally,

= 8000 + 2880

= 10,880 Rs.

**∴** Wrist watch price was,

= 10,880 – 10, 400

= 480 Rs.

Thus, the price of the watch will be Rs. 480

**Question no – (15) **

**Solution : **

We know that,

Simple Interest (S.I.) = (P × R × T/100)

**∴** Interest of Rs. 20000,

= 20,000 × 10 × 1/100

= 2000 Rs.

**∴** 30% of interest,

= 30/100 × 2000

= 600 Rs.

**∴** His annual income,

= 2000 – 600

= 1400 Rs.

Hence, Mr. Sharma annual income will be Rs. 1400

**Next chapter solution : **

👉 Chapter 14 👈