Add 3/7 and 21/18
1st number: 3/7, 2nd number: 1 3/18
3/7 + 21/18 is 67/42.
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,
3/7 = 3 × 18/7 × 18 = 54/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Add the two like fractions:
54/126 + 147/126 = 54 + 147/126 = 201/126 - 201/126 simplified gives 67/42
- So, 3/7 + 21/18 = 67/42
In mixed form: 125/42
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