Subtract 25/28 from 18/21
18/21 - 25/28 is -1/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
25/28 = 25 × 3/28 × 3 = 75/84 - Subtract the two like fractions:
72/84 - 75/84 = 72 - 75/84 = -3/84 - After reducing the fraction, the answer is -1/28
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