Subtract 12/18 from 21/7
1st number: 3 0/7, 2nd number: 12/18
21/7 - 12/18 is 7/3.
Steps for subtracting 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,
12/18 = 12 × 7/18 × 7 = 84/126 - Subtract the two like fractions:
378/126 - 84/126 = 378 - 84/126 = 294/126 - After reducing the fraction, the answer is 7/3
- In mixed form: 21/3
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