Subtract 18/12 from 10/21
1st number: 10/21, 2nd number: 1 6/12
10/21 - 18/12 is -43/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
10/21 = 10 × 4/21 × 4 = 40/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
18/12 = 18 × 7/12 × 7 = 126/84 - Subtract the two like fractions:
40/84 - 126/84 = 40 - 126/84 = -86/84 - After reducing the fraction, the answer is -43/42
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