Subtract 21/42 from 12/25
12/25 - 21/42 is -1/50.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 25 and 42 is 1050
Next, find the equivalent fraction of both fractional numbers with denominator 1050 - For the 1st fraction, since 25 × 42 = 1050,
12/25 = 12 × 42/25 × 42 = 504/1050 - Likewise, for the 2nd fraction, since 42 × 25 = 1050,
21/42 = 21 × 25/42 × 25 = 525/1050 - Subtract the two like fractions:
504/1050 - 525/1050 = 504 - 525/1050 = -21/1050 - After reducing the fraction, the answer is -1/50
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