Subtract 21/28 from 1/42
1/42 - 21/28 is -61/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
1/42 = 1 × 2/42 × 2 = 2/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Subtract the two like fractions:
2/84 - 63/84 = 2 - 63/84 = -61/84
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