Add 15/18 and 15/21
15/18 + 15/21 is 65/42.
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,
15/21 = 15 × 6/21 × 6 = 90/126 - Add the two like fractions:
105/126 + 90/126 = 105 + 90/126 = 195/126 - 195/126 simplified gives 65/42
- So, 15/18 + 15/21 = 65/42
In mixed form: 123/42
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