Subtract 21/48 from 1/42
1/42 - 21/48 is -139/336.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 48 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 42 × 8 = 336,
1/42 = 1 × 8/42 × 8 = 8/336 - Likewise, for the 2nd fraction, since 48 × 7 = 336,
21/48 = 21 × 7/48 × 7 = 147/336 - Subtract the two like fractions:
8/336 - 147/336 = 8 - 147/336 = -139/336
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