Add 21/7 and 21/18
1st number: 3 0/7, 2nd number: 1 3/18
21/7 + 21/18 is 25/6.
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,
21/18 = 21 × 7/18 × 7 = 147/126 - Add the two like fractions:
378/126 + 147/126 = 378 + 147/126 = 525/126 - 525/126 simplified gives 25/6
- So, 21/7 + 21/18 = 25/6
In mixed form: 41/6
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