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