Answers

Subtract 1/72 from 18/42

18/42 - 1/72 is 209/504.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 72 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 42 × 12 = 504,
   18/42 = 18 × 12/42 × 12 = 216/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   1/72 = 1 × 7/72 × 7 = 7/504
4. Subtract the two like fractions:
   216/504 - 7/504 = 216 - 7/504 = 209/504

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