Add 21/84 and 15/18
21/84 + 15/18 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
15/18 = 15 × 14/18 × 14 = 210/252 - Add the two like fractions:
63/252 + 210/252 = 63 + 210/252 = 273/252 - 273/252 simplified gives 13/12
- So, 21/84 + 15/18 = 13/12
In mixed form: 11/12
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