Subtract 20/72 from 7/90
7/90 - 20/72 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
7/90 = 7 × 4/90 × 4 = 28/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
20/72 = 20 × 5/72 × 5 = 100/360 - Subtract the two like fractions:
28/360 - 100/360 = 28 - 100/360 = -72/360 - After reducing the fraction, the answer is -1/5
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