Subtract 72/63 from 21/42
1st number: 21/42, 2nd number: 1 9/63
21/42 - 72/63 is -9/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
72/63 = 72 × 2/63 × 2 = 144/126 - Subtract the two like fractions:
63/126 - 144/126 = 63 - 144/126 = -81/126 - After reducing the fraction, the answer is -9/14
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