Subtract 21/84 from 18/28
18/28 - 21/84 is 11/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
18/28 = 18 × 3/28 × 3 = 54/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Subtract the two like fractions:
54/84 - 21/84 = 54 - 21/84 = 33/84 - After reducing the fraction, the answer is 11/28
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