Add 15/21 and 18/28
15/21 + 18/28 is 19/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Add the two like fractions:
60/84 + 54/84 = 60 + 54/84 = 114/84 - 114/84 simplified gives 19/14
- So, 15/21 + 18/28 = 19/14
In mixed form: 15/14
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