CLASS-5
SUBTRACTION OF FRACTION
SUBTRACTION OF FRACTION -
To subtract fractions, you also need to have a common denominator. The common denominator is the least common multiple of the denominators of the fractions being subtracted.
Once you have a common denominator, you can subtract the numerators of the fractions and simplify the resulting fraction, if necessary.
Here are the steps to subtract two fractions:
- Find the least common multiple (LCM) of the denominators.
- Rewrite each fraction with the common denominator.
- Subtract the numerators of the fractions.
- Simplify the resulting fraction, if necessary.
To subtract fractions, you also need to have a common denominator. The common denominator is the least common multiple of the denominators of the fractions being subtracted.
Once you have a common denominator, you can subtract the numerators of the fractions and simplify the resulting fraction, if necessary.
When you are subtracting two or more fractions, first change all the fractions to their equivalent fractions with common denominator (which is the L.C.M. of the denominators of the fractions) and then subtract.
For example, let's say you want to subtract 2/5 from 3/4:
- The least common multiple of 5 and 4 is 20.
- Rewrite 2/5 and 3/4 with a denominator of 20: 2/5 = 8/20, 3/4 = 15/20.
- Subtract the numerators: 15/20 - 8/20 = 7/20.
- The resulting fraction is already in its simplest form, so the answer is 7/20.
So, 3/4 - 2/5 = 7/20.
Example.1) Subtract the following fractions -
15 17
------- - -------
12 24
Ans.)
15 17
------- - -------
12 24
First we need to find LCM of denominator of fraction.
15 17
------- - -------
12 24
{(24 ÷ 12) X 15} - {(24 ÷ 24) X 17}
= -----------------------------------
24
(2 X 15) - (1 X 17)
= ---------------------
24
(30 - 17)
= ------------
24
13
= -------- (Ans.)
24
Example.2) Subtract the following fractions -
11 13
------- - -------
30 45
Ans.) First we need to find LCM of denominator of given fraction
11 13
------- - -------
30 45
{(90 ÷ 30) X 11} - {(90 ÷ 45) X 13}
= ----------------------------------
90
(3 X 11) - (2 X 13)
= ------------------------
90
(33 - 26)
= --------------
90
7
= ------- (Ans.)
90
Example.3) Subtract the following fractions -
7 5
3 ------- - 2 --------
9 18
Ans.) First we need to convert mix fraction to improper fraction, then we need to find LCM of denominator of given fraction
7 5
3 ------- - 2 --------
9 18
34 41
= -------- - --------
9 18
{(18 ÷ 9) X 34} - {(18 ÷ 18) X 41}
= ---------------------------------
18
(2 X 34) - (1 X 41)
= ------------------------
18
(68 - 41)
= ---------------
18
27 3 1
= ----------- = ----------- = 1 ------- (Ans.)
18 2 2