Subtract 18/12 from 21/35
1st number: 21/35, 2nd number: 1 6/12
21/35 - 18/12 is -9/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 35 × 12 = 420,
21/35 = 21 × 12/35 × 12 = 252/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
18/12 = 18 × 35/12 × 35 = 630/420 - Subtract the two like fractions:
252/420 - 630/420 = 252 - 630/420 = -378/420 - After reducing the fraction, the answer is -9/10
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