Subtract 21/28 from 18/84
18/84 - 21/28 is -15/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
18/84 = 18 × 1/84 × 1 = 18/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Subtract the two like fractions:
18/84 - 63/84 = 18 - 63/84 = -45/84 - After reducing the fraction, the answer is -15/28
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