Answers

Subtract 90/60 from 20/45

1^st number: 20/45, 2^nd number: 1 30/60

20/45 - 90/60 is -19/18.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 60 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 45 × 4 = 180,
   20/45 = 20 × 4/45 × 4 = 80/180
3. Likewise, for the 2nd fraction, since 60 × 3 = 180,
   90/60 = 90 × 3/60 × 3 = 270/180
4. Subtract the two like fractions:
   80/180 - 270/180 = 80 - 270/180 = -190/180
5. After reducing the fraction, the answer is -19/18

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