Add 42/15 and 80/21
1st number: 2 12/15, 2nd number: 3 17/21
42/15 + 80/21 is 694/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
42/15 = 42 × 7/15 × 7 = 294/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105 - Add the two like fractions:
294/105 + 400/105 = 294 + 400/105 = 694/105 - So, 42/15 + 80/21 = 694/105
In mixed form: 664/105
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