Subtract 18/84 from 21/63
21/63 - 18/84 is 5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 84 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 63 × 4 = 252,
21/63 = 21 × 4/63 × 4 = 84/252 - Likewise, for the 2nd fraction, since 84 × 3 = 252,
18/84 = 18 × 3/84 × 3 = 54/252 - Subtract the two like fractions:
84/252 - 54/252 = 84 - 54/252 = 30/252 - After reducing the fraction, the answer is 5/42
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