Subtract 63/42 from 9/21
1st number: 9/21, 2nd number: 1 21/42
9/21 - 63/42 is -15/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
9/21 = 9 × 2/21 × 2 = 18/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
63/42 = 63 × 1/42 × 1 = 63/42 - Subtract the two like fractions:
18/42 - 63/42 = 18 - 63/42 = -45/42 - After reducing the fraction, the answer is -15/14
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