Add 21/28 and 72/20
1st number: 21/28, 2nd number: 3 12/20
21/28 + 72/20 is 87/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
72/20 = 72 × 7/20 × 7 = 504/140 - Add the two like fractions:
105/140 + 504/140 = 105 + 504/140 = 609/140 - 609/140 simplified gives 87/20
- So, 21/28 + 72/20 = 87/20
In mixed form: 47/20
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