Add 21/60 and 63/90
21/60 + 63/90 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 60 × 3 = 180,
21/60 = 21 × 3/60 × 3 = 63/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
63/90 = 63 × 2/90 × 2 = 126/180 - Add the two like fractions:
63/180 + 126/180 = 63 + 126/180 = 189/180 - 189/180 simplified gives 21/20
- So, 21/60 + 63/90 = 21/20
In mixed form: 11/20
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