Add 72/21 and 36/12
1st number: 3 9/21, 2nd number: 3 0/12
72/21 + 36/12 is 45/7.
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,
36/12 = 36 × 7/12 × 7 = 252/84 - Add the two like fractions:
288/84 + 252/84 = 288 + 252/84 = 540/84 - 540/84 simplified gives 45/7
- So, 72/21 + 36/12 = 45/7
In mixed form: 63/7
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