Subtract 40/28 from 21/18
1st number: 1 3/18, 2nd number: 1 12/28
21/18 - 40/28 is -11/42.
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,
21/18 = 21 × 14/18 × 14 = 294/252 - Likewise, for the 2nd fraction, since 28 × 9 = 252,
40/28 = 40 × 9/28 × 9 = 360/252 - Subtract the two like fractions:
294/252 - 360/252 = 294 - 360/252 = -66/252 - After reducing the fraction, the answer is -11/42
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