Subtracting Rational Numbers, deals with various concepts which are as under:-
- Subtracting Rational Numbers When Denominators are Equal
- Subtracting Rational Numbers When Denominators are Unequal
Subtracting Rational Numbers When Denominators are Equal
Question 1
Subtract:
13/7 – 8/7
Explanation
Difference of Rational Numbers when Denominators are equal
Question 2
Subtract:
34/13 – 12/13
Explanation
Difference of Rational Numbers when Denominators are equal
Subtracting Rational Numbers When Denominators are Unequal
Question 3
Subtract:
3/4 – 2/7
Explanation
To subtract two Rational Numbers with different Denominators, first we will find the LCM of both the Denominators.
LCM of 4 and 7 is 28
Now we would divide such LCM by Denominator of first number and the result would be multiplied with both the numerator and denominator of such number
Divide LCM by the Denominator of first number
28 ÷ 4 = 7
We have to multiply , both the Numerator and Denominator of 3/4 by the quotient i.e, 7
Divide LCM by the Denominator of second number
28 ÷ 7 = 4
We have to multiply , both the Numerator and Denominator of 2/7 by the quotient i.e, 4
Question 4
Subtract:
5/4 – 3/5
Explanation
To subtract two Rational Numbers with different Denominators, first we will find the LCM of both the Denominators.
LCM of 4 and 5 is 20
Now we would divide such LCM by Denominator of first number and the result would be multiplied with both the numerator and denominator of such number
Divide LCM by the Denominator of first number
20 ÷ 4 = 5
We have to multiply , both the Numerator and Denominator of 5/4 by the quotient i.e, 5
Divide LCM by the Denominator of second number
20 ÷ 5 = 4
We have to multiply , both the Numerator and Denominator of 3/5 by the quotient i.e, 4
More Examples on Rational Numbers
Question 5
Find the number that should be added to -7/4 to make it 9/8?
Explanation
Question 6
Find the number that should be added to -5/6 to make it 6/5?
Explanation
Let x be the number, which needs to be added to -5/6 to get 6/5
Question 7
The sum of two Rational Number is -2 . If one of them is 3/2 then, other Rational Number is?
Explanation
Let, the other Rational Number be x
We are given that the sum of the two Rational Numbers is = -2
Hence, the other Rational Number is -7/2
Question 8
The sum of two Rational Number is -3/4 . If one of them is -4/12 then, other Rational Number is?
Explanation
Let, the other Rational Number be x
We are given that the sum of the two Rational Numbers is = -3/4
LCM of denominator in the two numbers , 4 and 12 is 12
Hence, the other Rational Number is -5/12