Add 21/15 and 18/42
1st number: 1 6/15, 2nd number: 18/42
21/15 + 18/42 is 64/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 15 × 14 = 210,
21/15 = 21 × 14/15 × 14 = 294/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
18/42 = 18 × 5/42 × 5 = 90/210 - Add the two like fractions:
294/210 + 90/210 = 294 + 90/210 = 384/210 - 384/210 simplified gives 64/35
- So, 21/15 + 18/42 = 64/35
In mixed form: 129/35
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