Answers

Subtract 45/25 from 18/72

1^st number: 18/72, 2^nd number: 1 20/25

18/72 - 45/25 is -31/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 25 is 1800
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1800
2. For the 1st fraction, since 72 × 25 = 1800,
   18/72 = 18 × 25/72 × 25 = 450/1800
3. Likewise, for the 2nd fraction, since 25 × 72 = 1800,
   45/25 = 45 × 72/25 × 72 = 3240/1800
4. Subtract the two like fractions:
   450/1800 - 3240/1800 = 450 - 3240/1800 = -2790/1800
5. After reducing the fraction, the answer is -31/20

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