Add 21/28 and 72/90
21/28 + 72/90 is 31/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
21/28 = 21 × 45/28 × 45 = 945/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
72/90 = 72 × 14/90 × 14 = 1008/1260 - Add the two like fractions:
945/1260 + 1008/1260 = 945 + 1008/1260 = 1953/1260 - 1953/1260 simplified gives 31/20
- So, 21/28 + 72/90 = 31/20
In mixed form: 111/20
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