Answers

Subtract 18/72 from 21/4

1^st number: 5 1/4, 2^nd number: 18/72

21/4 - 18/72 is 5/1.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 4 and 72 is 72
   
   Next, find the equivalent fraction of both fractional numbers with denominator 72
2. For the 1st fraction, since 4 × 18 = 72,
   21/4 = 21 × 18/4 × 18 = 378/72
3. Likewise, for the 2nd fraction, since 72 × 1 = 72,
   18/72 = 18 × 1/72 × 1 = 18/72
4. Subtract the two like fractions:
   378/72 - 18/72 = 378 - 18/72 = 360/72
5. After reducing the fraction, the answer is 5/1

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