Subtract 21/42 from 42/48
42/48 - 21/42 is 3/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 48 and 42 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 48 × 7 = 336,
42/48 = 42 × 7/48 × 7 = 294/336 - Likewise, for the 2nd fraction, since 42 × 8 = 336,
21/42 = 21 × 8/42 × 8 = 168/336 - Subtract the two like fractions:
294/336 - 168/336 = 294 - 168/336 = 126/336 - After reducing the fraction, the answer is 3/8
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