Add 81/42 and 20/15
1st number: 1 39/42, 2nd number: 1 5/15
81/42 + 20/15 is 137/42.
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,
81/42 = 81 × 5/42 × 5 = 405/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
20/15 = 20 × 14/15 × 14 = 280/210 - Add the two like fractions:
405/210 + 280/210 = 405 + 280/210 = 685/210 - 685/210 simplified gives 137/42
- So, 81/42 + 20/15 = 137/42
In mixed form: 311/42
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