Add 21/72 and 12/9
1st number: 21/72, 2nd number: 1 3/9
21/72 + 12/9 is 13/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
12/9 = 12 × 8/9 × 8 = 96/72 - Add the two like fractions:
21/72 + 96/72 = 21 + 96/72 = 117/72 - 117/72 simplified gives 13/8
- So, 21/72 + 12/9 = 13/8
In mixed form: 15/8
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