ML Aggarwal Simple and Compound Interest Exe-8.3 Class 8 ICSE Ch-8 Maths Solutions

ML Aggarwal Simple and Compound Interest Exe-8.3 Class 8 ICSE Ch-8 Maths Solutions. We Provide Step by Step Answer of  Exe-8.3 Questions for Simple and Compound Interest as council prescribe guideline for upcoming board exam. Visit official Website CISCE for detail information about ICSE Board Class-8.

ML Aggarwal Simple and Compound Interest Exe-8.3 Class 8 ICSE Maths Solutions

Board ICSE
Publications Avichal Publishig Company (APC)
Subject Maths
Class 8th
Chapter-8 Simple and Compound Interest
Writer ML Aggarwal
Book Name Understanding
Topics Solution of Exe-8.3 Questions
Edition 2023-2024

Simple and Compound Interest Exe-8.3

ML Aggarwal Class 8 ICSE Maths Solutions

Page-144

Question 1. Calculate the amount and compound interest on

(i) ₹15000 for 2 years at 10% per annum compounded annually.
(ii) ₹156250 for 112 years at 8% per annum compounded half-yearly.
(iii) ₹ 100000 for 9 months at 4% per annum compounded quarterly.

Answer:

(i) Principal (P) = Rs 15000

Rate (R) = 10% p.a.

Period (n) = 2 years

Amount (A) = P {1 + (R / 100)}n

= Rs 15000 {1 + (10 / 100)}2

= Rs 15000 × (11 / 10) × (11 / 10)

= Rs 18150

Compound interest = Amount – Principal

= Rs 18150 – 15000

= Rs 3150

(ii) Principal (P) = Rs 156250

Rate (R) = 8% p.a. or 4% half-yearly

Period (n) = 1(1/2)years

= 3 half-year

Amount (A) = P {1 + (R / 100)}n

= Rs 156250 {1 + (4 / 100)}3

= Rs 156250 × (26 / 25)3

= Rs 156250 × (26 / 25) × (26 / 25) × (26 / 25)

= Rs 175760

Compound interest = Amount – Principal

= Rs 175760 – Rs 156250

= Rs 19510

(iii) ₹ 100000 for 9 months at 4% per annum compounded quarterly.

Principal (P) = ₹ 100000

Rate of interest = 4% p.a. or 1% quarterly

Period (n) = 9 months or 3 quarters

A=P(1+r/100)n

=100000(1+1/100)3=100000(1+1/100)3

By further calculation

= 100000 × 101/100 × 101/100 × 101/100

= ₹ 103030.10

Here

CI = A – P

Substituting the values

= 103030.10 – 100000

= ₹ 3030.10

Question 2. Find the difference between the simple interest and compound interest on ₹4800 for 2 years at 5% per annum, compound interest being reckoned annually.

Answer:

Principal (P) = Rs 4800

Rate (R) = 5% p.a.

Period (n) = 2 years

S.I. = PRT / 100

= (4800 × 5 × 2) / 100

= Rs 480

Amount (A) = P {1 + (R / 100)}n

= Rs 4800 {1 + (5 / 100)}2

= Rs 4800 × (21 / 20) × (21 / 20)

= Rs 5292

Compound interest = Amount – Principal

= Rs 5292 – Rs 4800

= Rs 492

Difference in compound interest and simple interest = Rs 492 – Rs 480

= Rs 12


Simple and Compound Interest Exe-8.3

ML Aggarwal Class 8 ICSE Maths Solutions

Page-145

Question 3. Find the compound interest on ₹3125 for 3 years if the rates of interest for the first, second and third year are respectively 4%, 5% and 6% per annum.

Answer:

Principal (P) = Rs 3125

Rate of interest for continuous 3 years = 4%, 5%, 6%

Period (n) = 3 years

Amount = P {1 + (r / 100)}n

= 3125 {1 + (4 / 100)} {1 + (5 / 100)} {1 + (6 / 100)}

= 3125 × (26 / 25) × (21 / 20) × (53 / 50)

= Rs 14469 / 4

= Rs 3617.25

Compound interest = Amount – Principal

= Rs 3617. 25 – Rs 3125

= Rs 492. 25

Question 4. Kamla borrowed ₹26400 from a Bank to buy a scooter at a rate of 15% p.a. compounded yearly. What amount will she pay at the end of 2 years and 4 months to clear the loan?

Answer:

Money borrowed (P) = Rs 26400

Rate (R) = 15% p.a.

Period (n) = 2 years 4 months

= 2(4/12)

= 2 (1/3)years

Amount = P {1 + (R / 100)}n

= Rs 26400 {1 + (5 / 100)2} × [1 + {15 / (3 × 100)}]1

= Rs 26400 × (23 / 20) × (23 / 20) × (21 / 20)

We get,

= Rs 366597 / 10

= Rs 36659.70

Question 5. Anil borrowed ₹18000 from Rakesh at 8% per annum simple interest for 2 years. If Anil had borrowed this sum at 8% per annum compound interest, what extra amount would he has to pay?

Answer:

Money borrowed (P) = Rs 18000

Rate (R) = 8% p.a.

Time (n) = 2 years

Simple Interest = PRT / 100

= Rs (18000 × 8 × 2) / 100

= Rs 2880

A = P {1 + (R / 100)}n

= Rs 18000 {1 + (8 / 100)}2

= Rs 18000 × (27 / 25)2

= Rs 18000 × (27 / 25) × (27 / 25)

= Rs 104976 / 5

= Rs 20995.20

Compound interest = Amount – Principal

= Rs 20995.20 – Rs 18000

= Rs 2995.20

Difference between compound interest and simple interest

= Rs 2995.20 – Rs 2880

= Rs 115.20

Question 6. Mukesh borrowed 775000 from a bank. If the rate of interest is 12% per annum, find the amount he would be paying after 1(1/2) years if the interest is

(i) compounded annually
(ii) compounded half-yearly.

Answer:

Money borrowed (P) = Rs 75000

Rate (R) = 12% p.a. or 6% half- yearly

Period (n) = 1(1/2)years or 3 half-years

(i) When the interest compounded yearly

Amount (A) = P {1 + (R / 100)}n

= Rs 75000 {1 + (12 / 100)} {1 + (6 / 100)}

= Rs 75000 × (28 / 25) × (53 / 50)

= Rs 89040

(ii) When the interest compounded half-yearly

Amount = Rs 75000 {1 + (6 / 100)}3

= Rs 75000 × (53 / 50)3

= Rs 75000 × (53 / 50) × (53 / 50) × (53 / 50)

= Rs 446631 / 5

= Rs 89326.20

Question 7. Aryaman invested ₹10000 in a company, he would be paid interest at 7% per annum compounded annually. Find

(i) the amount received by him at the end of 2 years.
(ii) the interest for the 3rd year.

Answer:

(i) Investment to a company (P) = Rs 10000

Rate of interest (R) = 7% p.a.

Period (n) = 2 years

Amount (A) = P {1 + (R / 100)}n

= Rs 10000 {1 + (7 / 100)}2

= Rs 10000 × (107 / 100) × (107 / 100)

= Rs 11449

(ii) Amount after 3rd year = Rs 11449 × (107 / 100)

= Rs 12250.43

Interest on the 3rd year = Rs 12250.43 – 11449

= Rs 801.43

Question 8. What sum of money will amount to ₹9261 in 3 years at 5% per annum compound interest?

Answer:

Amount (A) = Rs 9261

Rate of interest = 5% p.a.

Time (T) = 3 years

Principal (P) =?

A = P {1 + (r / 100)}t

9261 = P {1 + (5 / 100)}3

9261 = P (21 / 20)3

P = (9261 × 20 × 20 × 20) / (21 × 21 × 21)

= Rs 8000

hence, the sum of money = Rs 8000

Question 9. What sum invested for 112 years compounded half-yearly at the rate 8% p.a. will amount to ₹ 140608?

Answer:

Amount (A) = Rs 140608

Rate (R) = 8% p.a. = 4% half-yearly

Period (n) = 1(1/2)years = 3 half-year

A = P {1 + (R / 100)}n

140608 = P {1 + (4 / 100)}3

140608 = P (26 / 25)3

P = 140608 × (25 / 26) × (25 / 26) × (25 / 26)

P = Rs 125000

Principal = Rs 125000

Question 10. At what rate percent will ₹2000 amount to ₹2315·25 in 3 years at compound interest?

Answer:

Principal (P) = Rs 2000

Amount (A) = Rs 2315.25

Period (n) = 3 years

Let the rate of interest be r% p.a.

A / P = {1 + (r / 100)}n

2315.25 / 2000 = {1 + (r / 100)}3

{1 + (r / 100)}3 = (231525) / (100 × 2000)

{1 + (r / 100)}3 = 9261 / 8000

{1 + (r / 100)}3 = (21 / 20)3

1 + (r / 100) = 21 / 20

r / 100 = (21 / 20) – 1

r / 100 = 1 / 20

r = 100 / 20

r = 5

Hence, rate of interest = 5% p.a.

Question 11. If ₹40000 amounts to ₹46305 in 112 years, compound interest payable half-yearly, find the rate of interest per annum.

Answer:

Principal (P) = Rs 40000

Amount (A) = Rs 46305

Period (n) = 1(1/2)years = 3/2 years

So half yearly, 2n = 2 × (3/2) = 3 years.

Let the rate of interest be r% p.a.

A / P = (1 + r / 100)n

46305 / 40000 = (1 + r / 100)3

(1 + r / 100)3 = 46305 / 40000

(1 + r / 100)3 = 9261 / 8000

(1 + r / 100)3 = (21 / 20)3

(1 + r / 100) = (21 / 20)

r / 100 = (21 / 20) – 1

r / 100 = 1 / 20

r = 100 / 20

r = 5

Hence, rate of interest = 5% for half year.

So, 2 × 5 = 10% per annum.

Question 12. In what time will ₹15625 amount to ₹ 17576 at 4% per annum compound interest?

Answer:

Amount (A) = Rs 17576

Principal (P) = Rs 15625

Rate (R) = 4% p.a.

A / P = {1 + (r / 100)}n

17576 / 15625 = {1 + (4 / 100)}n

(26 / 25)3 = (26 / 25)n

n = 3

Hence, time = 3 years

Question 13. ₹ 16000 invested at 10% p.a. compounded semi-annually, amounts to ₹18522. Find the time period of investment.

Answer:

Principal (P) = Rs 16000

Amount (A) = Rs 18522

Rate (R) = 10% p.a. or 5% semi-annually

A / P = {1 + (r / 100)}n

18522 / 16000 = {1 + (5 / 100)}n

9261 / 8000 = (21 / 20)n

(21 / 20)3 = (21 / 20)n

n = 3 half years

Hence,

Time = 3 / 2 = 1(1/2)years

—  : End of ML Aggarwal Simple and Compound Interest Exe-8.3 Class 8 ICSE Maths Solutions :–

Return to –  ML Aggarwal Maths Solutions for ICSE Class -8

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