Students can Download Class 8 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 to clear all their doubts, score well in final exams.
Karnataka State Syllabus 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 ₹ 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 Rs. 100 The money spent is Rs. 82.
∴ The amount remaining is 100 – 82=Rs. 18.
If the remaining money is Rs. 18 the money, in the beginning, is Rs. 100.
If the remaining money is Rs. 360 the money in the beginning is
= \(\frac { 100 }{ 18 }\) × 360 = 2000
Verification :
\(\frac { 82}{ 100 }\) × 2000 = 1640
Money remained = 2000 – 1640 = Rs. 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 ₹ 100.
Then Akshay’s income is (100 – 20) = ₹ 80.
If Akshay’s income is ₹ 80.
Ajay’s income is ₹ 100.
If Akshay’s income is ₹ 1 Ajay’s income is
Changing the scale to 100.
Ajay’s income is ₹ 100
Akshay’s income is
= 
∴ 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 ₹ 384 find his weekly earning.
Answer:
Let his weekly earning be Rs. 100.
His expenditure is Rs. 84.
Therefore his savings is (100 – 84) = Rs. 16
If the savings is Rs. 16 then the income is Rs. 100.
If the savings is Rs. 384 then the income is
= \(\frac { 100 }{ 16 }\) × 384 = Rs.2400
∴ His weekly earning is Rs. 2400.
Question 5.
A factory announces a bonus of 10% of its employees. If an employee gets ₹ 10,780 find his actual salary.
Answer:
Let the salary of the employee be Rs. 100.
He gets a bonus of Rs. 10.
He gets 100 + 10 = Rs. 110 including bonus.
∴ If the employee gets Rs. 10.780 his salary is
= \(\frac { 100 }{ 110 }\) × 10780 = 9800
∴ The salary of the employee is Rs. 9800