Add 81/15 and 20/42
1st number: 5 6/15, 2nd number: 20/42
81/15 + 20/42 is 617/105.
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,
81/15 = 81 × 14/15 × 14 = 1134/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210 - Add the two like fractions:
1134/210 + 100/210 = 1134 + 100/210 = 1234/210 - 1234/210 simplified gives 617/105
- So, 81/15 + 20/42 = 617/105
In mixed form: 592/105
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