Answers

Subtract 63/7 from 90/20

1^st number: 4 10/20, 2^nd number: 9 0/7

90/20 - 63/7 is -9/2.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 7 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 20 × 7 = 140,
   90/20 = 90 × 7/20 × 7 = 630/140
3. Likewise, for the 2nd fraction, since 7 × 20 = 140,
   63/7 = 63 × 20/7 × 20 = 1260/140
4. Subtract the two like fractions:
   630/140 - 1260/140 = 630 - 1260/140 = -630/140
5. After reducing the fraction, the answer is -9/2

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