Subtract 72/36 from 20/42
1st number: 20/42, 2nd number: 2 0/36
20/42 - 72/36 is -32/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 42 × 6 = 252,
20/42 = 20 × 6/42 × 6 = 120/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
72/36 = 72 × 7/36 × 7 = 504/252 - Subtract the two like fractions:
120/252 - 504/252 = 120 - 504/252 = -384/252 - After reducing the fraction, the answer is -32/21
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