Subtract 90/72 from 28/90
1st number: 28/90, 2nd number: 1 18/72
28/90 - 90/72 is -169/180.
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,
28/90 = 28 × 4/90 × 4 = 112/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Subtract the two like fractions:
112/360 - 450/360 = 112 - 450/360 = -338/360 - After reducing the fraction, the answer is -169/180
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