Students can Download Class 8 Maths Chapter 9 Commercial Arithmetic Ex 9.5 Questions and Answers, Notes Pdf, KSEEB Solutions for Class 8 Maths helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.

## Karnataka State Syllabus Class 8 Maths Chapter 9 Commercial Arithmetic Ex 9.5

Question 1.

Find the simple interest on Rs. 2500 for 4 years at 6 % per annum.

Answer:

P = Rs. 2500

T = 4 years

Simple interest is Rs. 625.

Question 2.

Find the simple interest on Rs. 3500 at the rate of 214% per annum for 165 days.

Answer:

P = Rs. 3500

Simple interest = Rs. 39.55.

Question 3.

In what period will Rs. 5200 amounts to Rs. 7,384 at 12% per annum simple interest?

Answer:

P = Rs. 5200

Amount = Rs. 7384

R = 12%

T = ?

Simple interest = Amount – principal = 7384 – 5200 = Rs. 2184

If amounts to Rs. 7,384 in 3.5 years

Question 4.

Ramya borrowed a loan from a bank for buying a computer. After 4 years she paid Rs. 26,640 and settled the account. If the rate of interest is 12% per annum what was the sum she borrowed?

Answer:

T = 4 years

R = 12%

After 4 years she paid Rs. 26,640.

This is nothing but amount.

Let the principal borrowed be R Amount = principal + S.I.

∴ Simple interest = Amount – principal S.I. = 26,640 – P

The principal borrowed – Rs. 18,000

Question 5.

A sum of money triples itself in 8 years. Find the rate of interest.

Answer:

Let the principal be x. It amounts to 3x in 8 years.

Amount = principal + simple interest

∴ Simple interest = Amount – principal = 3x – x = 2x

R = 25%