Add 81/42 and 15/18
1st number: 1 39/42, 2nd number: 15/18
81/42 + 15/18 is 58/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
81/42 = 81 × 3/42 × 3 = 243/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Add the two like fractions:
243/126 + 105/126 = 243 + 105/126 = 348/126 - 348/126 simplified gives 58/21
- So, 81/42 + 15/18 = 58/21
In mixed form: 216/21
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