Answers

Add 28/90 and 90/21

1^st number: 28/90, 2^nd number: 4 6/21

28/90 + 90/21 is 1448/315.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 21 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   28/90 = 28 × 7/90 × 7 = 196/630
3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
   90/21 = 90 × 30/21 × 30 = 2700/630
4. Add the two like fractions:
   196/630 + 2700/630 = 196 + 2700/630 = 2896/630
5. 2896/630 simplified gives 1448/315
6. So, 28/90 + 90/21 = 1448/315
   In mixed form: 4188/315

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