Answers

Add 90/5 and 42/21

1^st number: 18 0/5, 2^nd number: 2 0/21

90/5 + 42/21 is 20/1.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 5 and 21 is 105
   
   Next, find the equivalent fraction of both fractional numbers with denominator 105
2. For the 1st fraction, since 5 × 21 = 105,
   90/5 = 90 × 21/5 × 21 = 1890/105
3. Likewise, for the 2nd fraction, since 21 × 5 = 105,
   42/21 = 42 × 5/21 × 5 = 210/105
4. Add the two like fractions:
   1890/105 + 210/105 = 1890 + 210/105 = 2100/105
5. 2100/105 simplified gives 20/1
6. So, 90/5 + 42/21 = 20/1

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