Subtract 72/80 from 9/90
9/90 - 72/80 is -4/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
9/90 = 9 × 8/90 × 8 = 72/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
72/80 = 72 × 9/80 × 9 = 648/720 - Subtract the two like fractions:
72/720 - 648/720 = 72 - 648/720 = -576/720 - After reducing the fraction, the answer is -4/5
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