Subtract 63/42 from 10/21
1st number: 10/21, 2nd number: 1 21/42
10/21 - 63/42 is -43/42.
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,
10/21 = 10 × 2/21 × 2 = 20/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
63/42 = 63 × 1/42 × 1 = 63/42 - Subtract the two like fractions:
20/42 - 63/42 = 20 - 63/42 = -43/42
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