Subtract 7/4 from 21/54
1st number: 21/54, 2nd number: 1 3/4
21/54 - 7/4 is -49/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 4 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108 - Likewise, for the 2nd fraction, since 4 × 27 = 108,
7/4 = 7 × 27/4 × 27 = 189/108 - Subtract the two like fractions:
42/108 - 189/108 = 42 - 189/108 = -147/108 - After reducing the fraction, the answer is -49/36
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