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%