Add 21/18 and 40/7
1st number: 1 3/18, 2nd number: 5 5/7
21/18 + 40/7 is 289/42.
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,
40/7 = 40 × 18/7 × 18 = 720/126 - Add the two like fractions:
147/126 + 720/126 = 147 + 720/126 = 867/126 - 867/126 simplified gives 289/42
- So, 21/18 + 40/7 = 289/42
In mixed form: 637/42
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