Subtract 28/90 from 20/40
20/40 - 28/90 is 17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
28/90 = 28 × 4/90 × 4 = 112/360 - Subtract the two like fractions:
180/360 - 112/360 = 180 - 112/360 = 68/360 - After reducing the fraction, the answer is 17/90
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