Subtract 21/28 from 3/18
3/18 - 21/28 is -7/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 28 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 18 × 14 = 252,
3/18 = 3 × 14/18 × 14 = 42/252 - Likewise, for the 2nd fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Subtract the two like fractions:
42/252 - 189/252 = 42 - 189/252 = -147/252 - After reducing the fraction, the answer is -7/12
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