Subtract 21/80 from 28/72
28/72 - 21/80 is 91/720.
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,
28/72 = 28 × 10/72 × 10 = 280/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Subtract the two like fractions:
280/720 - 189/720 = 280 - 189/720 = 91/720
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