Subtract 30/48 from 21/42
21/42 - 30/48 is -1/8.
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,
21/42 = 21 × 8/42 × 8 = 168/336 - Likewise, for the 2nd fraction, since 48 × 7 = 336,
30/48 = 30 × 7/48 × 7 = 210/336 - Subtract the two like fractions:
168/336 - 210/336 = 168 - 210/336 = -42/336 - After reducing the fraction, the answer is -1/8
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