Subtract 81/42 from 4/21
1st number: 4/21, 2nd number: 1 39/42
4/21 - 81/42 is -73/42.
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,
4/21 = 4 × 2/21 × 2 = 8/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Subtract the two like fractions:
8/42 - 81/42 = 8 - 81/42 = -73/42
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