Answers

Subtract 40/21 from 90/5

1^st number: 18 0/5, 2^nd number: 1 19/21

90/5 - 40/21 is 338/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 5 and 21 is 105
   
   Next, find the equivalent fraction of both fractional numbers with denominator 105
2. For the 1st fraction, since 5 × 21 = 105,
   90/5 = 90 × 21/5 × 21 = 1890/105
3. Likewise, for the 2nd fraction, since 21 × 5 = 105,
   40/21 = 40 × 5/21 × 5 = 200/105
4. Subtract the two like fractions:
   1890/105 - 200/105 = 1890 - 200/105 = 1690/105
5. After reducing the fraction, the answer is 338/21
6. In mixed form: 162/21

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