Subtract 72/80 from 20/72
20/72 - 72/80 is -28/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 72 × 10 = 720,
20/72 = 20 × 10/72 × 10 = 200/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
72/80 = 72 × 9/80 × 9 = 648/720 - Subtract the two like fractions:
200/720 - 648/720 = 200 - 648/720 = -448/720 - After reducing the fraction, the answer is -28/45
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