Subtract 42/48 from 21/54
21/54 - 42/48 is -35/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 48 is 432
Next, find the equivalent fraction of both fractional numbers with denominator 432 - For the 1st fraction, since 54 × 8 = 432,
21/54 = 21 × 8/54 × 8 = 168/432 - Likewise, for the 2nd fraction, since 48 × 9 = 432,
42/48 = 42 × 9/48 × 9 = 378/432 - Subtract the two like fractions:
168/432 - 378/432 = 168 - 378/432 = -210/432 - After reducing the fraction, the answer is -35/72
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