Add 21/72 and 7/9
21/72 + 7/9 is 77/72.
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,
7/9 = 7 × 8/9 × 8 = 56/72 - Add the two like fractions:
21/72 + 56/72 = 21 + 56/72 = 77/72 - So, 21/72 + 7/9 = 77/72
In mixed form: 15/72
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