Subtract 21/72 from 20/63
20/63 - 21/72 is 13/504.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 63 × 8 = 504,
20/63 = 20 × 8/63 × 8 = 160/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Subtract the two like fractions:
160/504 - 147/504 = 160 - 147/504 = 13/504
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