Subtract 54/36 from 21/42
1st number: 21/42, 2nd number: 1 18/36
21/42 - 54/36 is -1/1.
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,
21/42 = 21 × 6/42 × 6 = 126/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
54/36 = 54 × 7/36 × 7 = 378/252 - Subtract the two like fractions:
126/252 - 378/252 = 126 - 378/252 = -252/252 - After reducing the fraction, the answer is -1/1
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