Subtract 20/45 from 28/72
28/72 - 20/45 is -1/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 45 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
28/72 = 28 × 5/72 × 5 = 140/360 - Likewise, for the 2nd fraction, since 45 × 8 = 360,
20/45 = 20 × 8/45 × 8 = 160/360 - Subtract the two like fractions:
140/360 - 160/360 = 140 - 160/360 = -20/360 - After reducing the fraction, the answer is -1/18
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