Subtract 72/21 from 15/18
1st number: 15/18, 2nd number: 3 9/21
15/18 - 72/21 is -109/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
72/21 = 72 × 6/21 × 6 = 432/126 - Subtract the two like fractions:
105/126 - 432/126 = 105 - 432/126 = -327/126 - After reducing the fraction, the answer is -109/42
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