Add and subtract fractions :
Whenever we want to add or subtract two or more fractions, first we have to check whether their denominators are same or not.
Let us see some example problems to understand the above concept.
Example 1 :
Add the fractions
Solution :
Since the denominators are not same, we have to take L.C.M in order to make the denominators same.
L.C.M of (4, 8) = 8
Multiply the numerator and denominator of the first fraction by 2.
(1/4) x (2/2) = 2/8
(1/4) + (3/8) = (2/8) + (3/8)
= (2+3)/8
= 5/8
Example 2 :
Add the fractions
Solution :
Since the denominators are not same, we have to take L.C.M in order to make the denominators same.
L.C.M of (4, 5) = 20
Multiply the numerator and denominator of the first fraction by 5.
Multiply the numerator and denominator of the second fraction by 4.
(3/4) x (5/5) = 15/20
(2/5) x (4/4) = 8/20
(15/20) + (8/20) = (15 + 8)/20
= 23/20
Since it is improper fraction, we have to make it is as mixed fraction.
Example 3 :
Subtract the fractions
Solution :
Since the denominators are not same, we have to take L.C.M in order to make the denominators same.
L.C.M of (8, 7) = 56
Multiply the numerator and denominator of the first fraction by 7.
Multiply the numerator and denominator of the second fraction by 8.
(5/8) x (7/7) = 35/56
(1/7) x (8/8) = 8/56
(35/56) + (8/56) = (35 + 8)/56
= 43/56
Example 4 :
Subtract the fractions
Solution :
Since the denominators are not same, we have to take L.C.M in order to make the denominators same.
L.C.M of (2, 3) = 6
Multiply the numerator and denominator of the first fraction by 3.
Multiply the numerator and denominator of the second fraction by 2.
(3/2) x (3/3) = 9/6
(4/3) x (2/2) = 8/6
(9/6) + (8/6) = (9 + 8)/6
= 17/6
Since it is improper fraction, we have to make it is as mixed fraction.
After having gone through the stuff given above, we hope that the students would have understood "Add and subtract fractions".
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