Subtract 75/72 from 20/21
1st number: 20/21, 2nd number: 1 3/72
20/21 - 75/72 is -5/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
20/21 = 20 × 24/21 × 24 = 480/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
75/72 = 75 × 7/72 × 7 = 525/504 - Subtract the two like fractions:
480/504 - 525/504 = 480 - 525/504 = -45/504 - After reducing the fraction, the answer is -5/56
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