Add 42/15 and 84/21
1st number: 2 12/15, 2nd number: 4 0/21
42/15 + 84/21 is 34/5.
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,
84/21 = 84 × 5/21 × 5 = 420/105 - Add the two like fractions:
294/105 + 420/105 = 294 + 420/105 = 714/105 - 714/105 simplified gives 34/5
- So, 42/15 + 84/21 = 34/5
In mixed form: 64/5
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