Add 21/72 and 9/8
1st number: 21/72, 2nd number: 1 1/8
21/72 + 9/8 is 17/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 8 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 8 × 9 = 72,
9/8 = 9 × 9/8 × 9 = 81/72 - Add the two like fractions:
21/72 + 81/72 = 21 + 81/72 = 102/72 - 102/72 simplified gives 17/12
- So, 21/72 + 9/8 = 17/12
In mixed form: 15/12
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