Add 81/42 and 21/18
1st number: 1 39/42, 2nd number: 1 3/18
81/42 + 21/18 is 65/21.
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,
21/18 = 21 × 7/18 × 7 = 147/126 - Add the two like fractions:
243/126 + 147/126 = 243 + 147/126 = 390/126 - 390/126 simplified gives 65/21
- So, 81/42 + 21/18 = 65/21
In mixed form: 32/21
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