Add 12/21 and 72/63
1st number: 12/21, 2nd number: 1 9/63
12/21 + 72/63 is 12/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
12/21 = 12 × 3/21 × 3 = 36/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
72/63 = 72 × 1/63 × 1 = 72/63 - Add the two like fractions:
36/63 + 72/63 = 36 + 72/63 = 108/63 - 108/63 simplified gives 12/7
- So, 12/21 + 72/63 = 12/7
In mixed form: 15/7
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