Subtract 42/36 from 7/21
1st number: 7/21, 2nd number: 1 6/36
7/21 - 42/36 is -5/6.
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,
7/21 = 7 × 12/21 × 12 = 84/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
42/36 = 42 × 7/36 × 7 = 294/252 - Subtract the two like fractions:
84/252 - 294/252 = 84 - 294/252 = -210/252 - After reducing the fraction, the answer is -5/6
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