Subtract 42/36 from 3/21
1st number: 3/21, 2nd number: 1 6/36
3/21 - 42/36 is -43/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
3/21 = 3 × 12/21 × 12 = 36/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
42/36 = 42 × 7/36 × 7 = 294/252 - Subtract the two like fractions:
36/252 - 294/252 = 36 - 294/252 = -258/252 - After reducing the fraction, the answer is -43/42
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