Subtract 21/36 from 8/42
8/42 - 21/36 is -11/28.
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,
8/42 = 8 × 6/42 × 6 = 48/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Subtract the two like fractions:
48/252 - 147/252 = 48 - 147/252 = -99/252 - After reducing the fraction, the answer is -11/28
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