Answers

Add 90/20 and 60/80

1^st number: 4 10/20, 2^nd number: 60/80

90/20 + 60/80 is 21/4.

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,
   60/80 = 60 × 1/80 × 1 = 60/80
4. Add the two like fractions:
   360/80 + 60/80 = 360 + 60/80 = 420/80
5. 420/80 simplified gives 21/4
6. So, 90/20 + 60/80 = 21/4
   In mixed form: 51/4

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