Answers

Subtract 9/20 from 9/45

9/45 - 9/20 is -1/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 20 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 45 × 4 = 180,
   9/45 = 9 × 4/45 × 4 = 36/180
3. Likewise, for the 2nd fraction, since 20 × 9 = 180,
   9/20 = 9 × 9/20 × 9 = 81/180
4. Subtract the two like fractions:
   36/180 - 81/180 = 36 - 81/180 = -45/180
5. After reducing the fraction, the answer is -1/4

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