Add 80/42 and 20/15
1st number: 1 38/42, 2nd number: 1 5/15
80/42 + 20/15 is 68/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
80/42 = 80 × 5/42 × 5 = 400/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
20/15 = 20 × 14/15 × 14 = 280/210 - Add the two like fractions:
400/210 + 280/210 = 400 + 280/210 = 680/210 - 680/210 simplified gives 68/21
- So, 80/42 + 20/15 = 68/21
In mixed form: 35/21
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