Subtract 1/42 from 21/48
21/48 - 1/42 is 139/336.
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,
21/48 = 21 × 7/48 × 7 = 147/336 - Likewise, for the 2nd fraction, since 42 × 8 = 336,
1/42 = 1 × 8/42 × 8 = 8/336 - Subtract the two like fractions:
147/336 - 8/336 = 147 - 8/336 = 139/336
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