Selina Concise Mathematics Class 7 ICSE Solutions Chapter 2 Rational Numbers

Selina Concise Mathematics Class 7 ICSE Solutions Chapter 2 Rational Numbers

Selina Concise Mathematics Class 7 ICSE Solutions Chapter 2 Rational Numbers

Selina Publishers Concise Mathematics Class 7 ICSE Solutions Chapter 2 Rational Numbers

EXERCISE 2 (A)

Question 1.

Write down a rational number whose numerator is the largest number of two digits and denominator is the smallest number of four digits.

Solution:

Largest two digit = 99

Smallest, number of four digit = 1000 Now numerator = 99 and denominator = 1000

∴ Rational number =   

Question 2.
Write the numerator of each of the following rational numbers:
 

Solution:
 

 

Question 3.
Write the denominator of each of the following rational numbers:
 

Solution:
 

Question 4.
Write down a rational number numerator (-5) x (-4) and denominator (28 – 27) x (8 – 5).
Solution:
 

Question 5.
 

Solution:
 

Question 6.
Separate positive and negative rational numbers from the following :
 

Solution:
 

 

Question 7.
Find three rational numbers equivalent to
 

Solution:
 

 

Question 8.
Which of the following are not rational numbers :
 

Solution:
 

Question 9.

Express each of the following integers as a rational number with denominator 7 :

(i) 5

(ii) -8
(iii) 0
(iv) -16
(v) 7

Solution:
 

 
Question 10.
Express  as a rational number with denominator:
Solution:
 

Question 11.
Express  as a rational number with numerator :
Solution:
 

Question 12.

Find x, such that:
 

Solution:
 

 
 
 

Question 13.
Express each of the following rational numbers to the lowest terms :
 

Solution:
 

 

Question 14.
Express each of the following rational numbers in the standard form.
 

Solution:
 

 

EXERCISE 2 (B)

Question 1.
Mark the following pairs of rational numbers on the separate number lines :
 

Solution:
 

 

Question 2.
Compare:
 

Solution:
 
 

 
 

Question 3.
Compare:
 
Solution:
 

 
 
 

Question 4.

Arrange the given rational numbers in ascending order :
 

Solution:
 
 

Question 5.
Arrange the given rational numbers in descending order:
 

Solution:
 

 

Question 6.
Fill in the blanks :
 

Solution:
 

 

EXERCISE 2 (C)

Question 1.
Add:
 

Solution:

 

 

Question 2.

Add:
 

Solution:

 

 
 
 

  Solution:

 

Question 3.

Evaluate:

 

Solution:
 

 
 

Question 4.
Evaluate:
 

Solution:

 

 
 

Question 5.
Subtract :
 

Solution:

 

 

Question 6.

Subtract :
 

Solution:
 

 
 
 

Question 7.

The sum of two rational numbers is  . If one of them is  , find the other.

Solution:
 

Question 8.
The sum of two rational numbers is  . If one of them is  , find the other.

Solution:
 

Question 9.

The sum of two rational numbers is -4. If one of them is  , find the other.
Solution:
 

Question 10.
What should be added to -3/6 to get   ?

Solution:
 

 

Question 11.

What should be added to to get 2?
Solution:
 

Question 12.
What should be subtracted from  to get 1?
Solution:
 

 

Question 13.
The sum of two numbers is  . If one of them is -2, find the other.

Solution:
 

Question 14.
What should be added to   to get  ?

Solution:
 

Question 15.
What should be subtracted from  to get ?

Solution:
 

EXERCISE 2 (D)

Question 1.
Evaluate:
 

Solution:
 

 
 

Question 2.
Multiply:
 

Solution:
 

 
 
 

Question 3.
Evaluate:
 

 

Solution:
 

 
 
 
 

Question 4.
Find the cost of 3 m cloth, if one metre cloth costs ₹325   .

Solution:
 

Question 5.
A bus is moving with a speed of 65   km per hour. How much distance will it cover in 1  hours.

Solution:

 

Question 6.

Divide:
 

Solution:
 

 

Question 7.
Evaluate:
 

Solution:
 

 
 

Question 8.
The product of two numbers is 14. If one of the numbers is , find the other.

Solution:
 

Question 9.
The cost of 11 pens is ₹3 

 . Find the cost of one pen.

Solution:

 
Question 10.
If 6 identical articles can be bought for ₹2  . Find the cost of each article.

Solution:
 

Question 11.
By what number should be multiplied so that the product is ?

Solution:
 

Question 12.
By what number should be divided so -15 that the result is ?

Solution:
 

Question 13.
Evaluate :
 

Solution:
 
Question 14.
Seven equal piece are made out of a rope 5 of 21  m. Find the length of each piece.

Solution:
 

EXERCISE 2 (E)

Question 1.

Evaluate:
 

Solution:
 

 
 
 
 
 
 
 

Question 2.
The sum of two rational numbers is  . If one of them is  , find the other,

Solution:
 

Question 3.
The sum of two rational numbers is -5. If one of them is  , find the other.

Solution:
 

Question 4.
What rational number should be added to  to get   

Solution:
 

 

Question 5.
What rational number should be added to  to get 2?

Solution:
 

Question 6.
What rational number should be subtracted from to get 

 

Solution:
 

Question 7.
What rational number should be subtracted from to get ?

Solution:
 

Question 8.

Evaluate:
 

Solution:
 

 
 
 
 

Question 9.
The product of two rational numbers is 24. If one of them is , find the other.

Solution:
 

Question 10.
By what rational number should we multiply   ,so that the product may be ?

Solution: