Add 21/18 and 81/7
1st number: 1 3/18, 2nd number: 11 4/7
21/18 + 81/7 is 535/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 7 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Likewise, for the 2nd fraction, since 7 × 18 = 126,
81/7 = 81 × 18/7 × 18 = 1458/126 - Add the two like fractions:
147/126 + 1458/126 = 147 + 1458/126 = 1605/126 - 1605/126 simplified gives 535/42
- So, 21/18 + 81/7 = 535/42
In mixed form: 1231/42
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