Subtract 72/18 from 21/12
1st number: 1 9/12, 2nd number: 4 0/18
21/12 - 72/18 is -9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
72/18 = 72 × 2/18 × 2 = 144/36 - Subtract the two like fractions:
63/36 - 144/36 = 63 - 144/36 = -81/36 - After reducing the fraction, the answer is -9/4
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