Answers

Subtract 7/20 from 8/45

8/45 - 7/20 is -31/180.

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,
   8/45 = 8 × 4/45 × 4 = 32/180
3. Likewise, for the 2nd fraction, since 20 × 9 = 180,
   7/20 = 7 × 9/20 × 9 = 63/180
4. Subtract the two like fractions:
   32/180 - 63/180 = 32 - 63/180 = -31/180

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