Add 21/28 and 15/18
21/28 + 15/18 is 19/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
15/18 = 15 × 14/18 × 14 = 210/252 - Add the two like fractions:
189/252 + 210/252 = 189 + 210/252 = 399/252 - 399/252 simplified gives 19/12
- So, 21/28 + 15/18 = 19/12
In mixed form: 17/12
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