Subtract 20/48 from 3/42
3/42 - 20/48 is -29/84.
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,
3/42 = 3 × 8/42 × 8 = 24/336 - Likewise, for the 2nd fraction, since 48 × 7 = 336,
20/48 = 20 × 7/48 × 7 = 140/336 - Subtract the two like fractions:
24/336 - 140/336 = 24 - 140/336 = -116/336 - After reducing the fraction, the answer is -29/84
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