Subtract 28/40 from 80/90
80/90 - 28/40 is 17/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
80/90 = 80 × 4/90 × 4 = 320/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
28/40 = 28 × 9/40 × 9 = 252/360 - Subtract the two like fractions:
320/360 - 252/360 = 320 - 252/360 = 68/360 - After reducing the fraction, the answer is 17/90
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