Answers

Subtract 4/20 from 7/45

7/45 - 4/20 is -2/45.

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,
   7/45 = 7 × 4/45 × 4 = 28/180
3. Likewise, for the 2nd fraction, since 20 × 9 = 180,
   4/20 = 4 × 9/20 × 9 = 36/180
4. Subtract the two like fractions:
   28/180 - 36/180 = 28 - 36/180 = -8/180
5. After reducing the fraction, the answer is -2/45

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