Subtract 20/21 from 5/72
5/72 - 20/21 is -445/504.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
5/72 = 5 × 7/72 × 7 = 35/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
20/21 = 20 × 24/21 × 24 = 480/504 - Subtract the two like fractions:
35/504 - 480/504 = 35 - 480/504 = -445/504
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