Subtract 42/48 from 1/21
1/21 - 42/48 is -139/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 48 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 21 × 16 = 336,
1/21 = 1 × 16/21 × 16 = 16/336 - Likewise, for the 2nd fraction, since 48 × 7 = 336,
42/48 = 42 × 7/48 × 7 = 294/336 - Subtract the two like fractions:
16/336 - 294/336 = 16 - 294/336 = -278/336 - After reducing the fraction, the answer is -139/168
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