Answers

Subtract 8/21 from 8/72

8/72 - 8/21 is -17/63.

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,
   8/72 = 8 × 7/72 × 7 = 56/504
3. Likewise, for the 2nd fraction, since 21 × 24 = 504,
   8/21 = 8 × 24/21 × 24 = 192/504
4. Subtract the two like fractions:
   56/504 - 192/504 = 56 - 192/504 = -136/504
5. After reducing the fraction, the answer is -17/63

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