Subtract 40/42 from 20/36
20/36 - 40/42 is -25/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Likewise, for the 2nd fraction, since 42 × 6 = 252,
40/42 = 40 × 6/42 × 6 = 240/252 - Subtract the two like fractions:
140/252 - 240/252 = 140 - 240/252 = -100/252 - After reducing the fraction, the answer is -25/63
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