Add 72/21 and 20/28
1st number: 3 9/21, 2nd number: 20/28
72/21 + 20/28 is 29/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
72/21 = 72 × 4/21 × 4 = 288/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
20/28 = 20 × 3/28 × 3 = 60/84 - Add the two like fractions:
288/84 + 60/84 = 288 + 60/84 = 348/84 - 348/84 simplified gives 29/7
- So, 72/21 + 20/28 = 29/7
In mixed form: 41/7
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