Answers

Add 90/20 and 30/80

1^st number: 4 10/20, 2^nd number: 30/80

90/20 + 30/80 is 39/8.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 80 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 20 × 4 = 80,
   90/20 = 90 × 4/20 × 4 = 360/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   30/80 = 30 × 1/80 × 1 = 30/80
4. Add the two like fractions:
   360/80 + 30/80 = 360 + 30/80 = 390/80
5. 390/80 simplified gives 39/8
6. So, 90/20 + 30/80 = 39/8
   In mixed form: 47/8

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