Subtract 16/18 from 28/40
28/40 - 16/18 is -17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
28/40 = 28 × 9/40 × 9 = 252/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
16/18 = 16 × 20/18 × 20 = 320/360 - Subtract the two like fractions:
252/360 - 320/360 = 252 - 320/360 = -68/360 - After reducing the fraction, the answer is -17/90
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