Add 15/18 and 21/72
15/18 + 21/72 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
15/18 = 15 × 4/18 × 4 = 60/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Add the two like fractions:
60/72 + 21/72 = 60 + 21/72 = 81/72 - 81/72 simplified gives 9/8
- So, 15/18 + 21/72 = 9/8
In mixed form: 11/8
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