Answers

Add 90/45 and 70/21

1^st number: 2 0/45, 2^nd number: 3 7/21

90/45 + 70/21 is 16/3.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 21 is 315
   
   Next, find the equivalent fraction of both fractional numbers with denominator 315
2. For the 1st fraction, since 45 × 7 = 315,
   90/45 = 90 × 7/45 × 7 = 630/315
3. Likewise, for the 2nd fraction, since 21 × 15 = 315,
   70/21 = 70 × 15/21 × 15 = 1050/315
4. Add the two like fractions:
   630/315 + 1050/315 = 630 + 1050/315 = 1680/315
5. 1680/315 simplified gives 16/3
6. So, 90/45 + 70/21 = 16/3
   In mixed form: 51/3

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