Add 15/18 and 18/21
15/18 + 18/21 is 71/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
18/21 = 18 × 6/21 × 6 = 108/126 - Add the two like fractions:
105/126 + 108/126 = 105 + 108/126 = 213/126 - 213/126 simplified gives 71/42
- So, 15/18 + 18/21 = 71/42
In mixed form: 129/42
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