Subtract 5/18 from 21/80
21/80 - 5/18 is -11/720.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
5/18 = 5 × 40/18 × 40 = 200/720 - Subtract the two like fractions:
189/720 - 200/720 = 189 - 200/720 = -11/720
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