Answers

Subtract 63/42 from 18/72

1^st number: 18/72, 2^nd number: 1 21/42

18/72 - 63/42 is -5/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 42 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 72 × 7 = 504,
   18/72 = 18 × 7/72 × 7 = 126/504
3. Likewise, for the 2nd fraction, since 42 × 12 = 504,
   63/42 = 63 × 12/42 × 12 = 756/504
4. Subtract the two like fractions:
   126/504 - 756/504 = 126 - 756/504 = -630/504
5. After reducing the fraction, the answer is -5/4

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