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.
\frac { 300 }{ 100 } × 900 = 270
The number of players who play carrom board = 60% of 900
\frac { 60}{ 100 } × 900 = 540
The number of players who play other games = 10% of 900
\frac { 10 }{ 100 } × 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
\frac { 100 }{ 18 } × 360 = 2000
Verification :
\frac { 82}{ 100 } × 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
\frac { 100 }{ 16 } × 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
\frac { 100 }{ 110 } × 10780 = 9800
∴ The salary of the employee is ₹ 9800