Add 15/21 and 42/18
1st number: 15/21, 2nd number: 2 6/18
15/21 + 42/18 is 64/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
15/21 = 15 × 6/21 × 6 = 90/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126 - Add the two like fractions:
90/126 + 294/126 = 90 + 294/126 = 384/126 - 384/126 simplified gives 64/21
- So, 15/21 + 42/18 = 64/21
In mixed form: 31/21
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