Subtract 21/12 from 25/42
1st number: 25/42, 2nd number: 1 9/12
25/42 - 21/12 is -97/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
25/42 = 25 × 2/42 × 2 = 50/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Subtract the two like fractions:
50/84 - 147/84 = 50 - 147/84 = -97/84
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