Subtract 28/90 from 9/80
9/80 - 28/90 is -143/720.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
9/80 = 9 × 9/80 × 9 = 81/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
28/90 = 28 × 8/90 × 8 = 224/720 - Subtract the two like fractions:
81/720 - 224/720 = 81 - 224/720 = -143/720
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