Add 72/21 and 15/12
1st number: 3 9/21, 2nd number: 1 3/12
72/21 + 15/12 is 131/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 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 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84 - Add the two like fractions:
288/84 + 105/84 = 288 + 105/84 = 393/84 - 393/84 simplified gives 131/28
- So, 72/21 + 15/12 = 131/28
In mixed form: 419/28
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