Subtract 72/18 from 21/28
1st number: 21/28, 2nd number: 4 0/18
21/28 - 72/18 is -13/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
72/18 = 72 × 14/18 × 14 = 1008/252 - Subtract the two like fractions:
189/252 - 1008/252 = 189 - 1008/252 = -819/252 - After reducing the fraction, the answer is -13/4
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