Subtract 28/72 from 1/90
1/90 - 28/72 is -17/45.
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,
1/90 = 1 × 4/90 × 4 = 4/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
28/72 = 28 × 5/72 × 5 = 140/360 - Subtract the two like fractions:
4/360 - 140/360 = 4 - 140/360 = -136/360 - After reducing the fraction, the answer is -17/45
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