Subtract 21/72 from 21/80
21/80 - 21/72 is -7/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 72 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 72 × 10 = 720,
21/72 = 21 × 10/72 × 10 = 210/720 - Subtract the two like fractions:
189/720 - 210/720 = 189 - 210/720 = -21/720 - After reducing the fraction, the answer is -7/240
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