Answers

Subtract 20/84 from 90/21

1^st number: 4 6/21, 2^nd number: 20/84

90/21 - 20/84 is 85/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   90/21 = 90 × 4/21 × 4 = 360/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   20/84 = 20 × 1/84 × 1 = 20/84
4. Subtract the two like fractions:
   360/84 - 20/84 = 360 - 20/84 = 340/84
5. After reducing the fraction, the answer is 85/21
6. In mixed form: 41/21

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