Students can Download Maths Chapter 9 Commercial Arithmetic Ex 9.1 Questions and Answers, Notes Pdf, KSEEB Solutions for Class 8 Maths helps you to revise the complete Karnataka State Board Syllabus and score more marks in your examinations.

## Karnataka Board Class 8 Maths Chapter 9 Commercial Arithmetic Ex 9.1

Question 1.

In a school 30% students play chess 60% play carrom and the rest play other games. If the total number of students in the school is 900 find the exact number of students who play each game.

Answer:

30% Students play chess. Total number of students is 900.

The number of players who play chess = 30% of 900.

= × 900 = 270

The number of players who play carrom board = 60% of 900

= × 900 = 540

The number of players who play other games = 10% of 900

= × 900 = 90

Question 2.

In a school function Rs. 360 remained after spending 82% of the money. How much money was there in the beginning? verify your answer.

Answer:

Let the money, in the beginning, be ₹ 100 The money spent is ₹ 82.

∴ The amount remaining is 100 – 82 = ₹ 18.

If the remaining money is ₹ 18 the money, in the beginning, is ₹ 100.

If the remaining money is ₹ 360 the money in the beginning is

= × 360 = 2000

Verification :

× 2000 = 1640

Money remained = 2000 – 1640 = ₹ 360.

Question 3.

Akshay’s income is 20% less than that of Ajay what percent is Ajay’s income more than that of Akshay?

Answer:

Let Ajay’s income be Rs. 100.

Then Akshay’s income is (100 – 20) = Rs. 80.

If Akshay’s income is Rs. 80.

Ajay’s income is Rs. 100.

If Akshay’s income is Rs. 1 Ajay’s income is

\(\frac{100}{80}\) × 1 = Rs. \(\frac { 100 }{ 80 }\)

Changing the scale to 100.

Ajay’s income is Rs. 100

Akshay’s income is

= \(\frac { 100 }{ 80 }\) × 100 = 125

∴ Ajay’s income is 125 – 100 = 25% more than that of Akshay.

Question 4.

A daily wage employee spends 84% of his weekly earning. If he saves Rs. 384 find his weekly earning.

Answer:

Let his weekly earning be ₹ 100.

His expenditure is ₹ 84.

Therefore his savings is (100 – 84) = ₹ 16

If the savings is ₹ 16 then the income is ₹ 100.

If the savings is ₹ 384 then the income is

= × 384 = ₹ 2400

∴ His weekly earning is ₹ 2400.

Question 5.

A factory announces a bonus of 10% its employees. If an employee gets Rs. 10,780 find his actual salary.

Answer:

Let the salary of the employee be ₹ 100.

He gets a bonus of ₹ 10.

He gets 100 + 10 = ₹ 110 including bonus.

∴ If the employee gets ₹ 10.780 his salary is

= × 10780 = 9800

∴ The salary of the employee is ₹ 9800