Answers

Subtract 5/21 from 7/72

7/72 - 5/21 is -71/504.

Steps for subtracting fractions

1. 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
2. For the 1st fraction, since 72 × 7 = 504,
   7/72 = 7 × 7/72 × 7 = 49/504
3. Likewise, for the 2nd fraction, since 21 × 24 = 504,
   5/21 = 5 × 24/21 × 24 = 120/504
4. Subtract the two like fractions:
   49/504 - 120/504 = 49 - 120/504 = -71/504

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