Subtract 18/4 from 7/21
1st number: 7/21, 2nd number: 4 2/4
7/21 - 18/4 is -25/6.
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,
7/21 = 7 × 4/21 × 4 = 28/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
18/4 = 18 × 21/4 × 21 = 378/84 - Subtract the two like fractions:
28/84 - 378/84 = 28 - 378/84 = -350/84 - After reducing the fraction, the answer is -25/6
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