Subtract 12/7 from 21/18
1st number: 1 3/18, 2nd number: 1 5/7
21/18 - 12/7 is -23/42.
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,
21/18 = 21 × 7/18 × 7 = 147/126 - Likewise, for the 2nd fraction, since 7 × 18 = 126,
12/7 = 12 × 18/7 × 18 = 216/126 - Subtract the two like fractions:
147/126 - 216/126 = 147 - 216/126 = -69/126 - After reducing the fraction, the answer is -23/42
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