Subtract 18/9 from 21/84
1st number: 21/84, 2nd number: 2 0/9
21/84 - 18/9 is -7/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
21/84 = 21 × 3/84 × 3 = 63/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
18/9 = 18 × 28/9 × 28 = 504/252 - Subtract the two like fractions:
63/252 - 504/252 = 63 - 504/252 = -441/252 - After reducing the fraction, the answer is -7/4
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