Add 21/7 and 8/18
1st number: 3 0/7, 2nd number: 8/18
21/7 + 8/18 is 31/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
21/7 = 21 × 18/7 × 18 = 378/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Add the two like fractions:
378/126 + 56/126 = 378 + 56/126 = 434/126 - 434/126 simplified gives 31/9
- So, 21/7 + 8/18 = 31/9
In mixed form: 34/9
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