Subtract 18/4 from 25/21
1st number: 1 4/21, 2nd number: 4 2/4
25/21 - 18/4 is -139/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
25/21 = 25 × 4/21 × 4 = 100/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
18/4 = 18 × 21/4 × 21 = 378/84 - Subtract the two like fractions:
100/84 - 378/84 = 100 - 378/84 = -278/84 - After reducing the fraction, the answer is -139/42
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