Add 72/21 and 63/12
1st number: 3 9/21, 2nd number: 5 3/12
72/21 + 63/12 is 243/28.
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,
63/12 = 63 × 7/12 × 7 = 441/84 - Add the two like fractions:
288/84 + 441/84 = 288 + 441/84 = 729/84 - 729/84 simplified gives 243/28
- So, 72/21 + 63/12 = 243/28
In mixed form: 819/28
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