Answers

Add 42/21 and 12/90

1^st number: 2 0/21, 2^nd number: 12/90

42/21 + 12/90 is 32/15.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 21 × 30 = 630,
   42/21 = 42 × 30/21 × 30 = 1260/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   12/90 = 12 × 7/90 × 7 = 84/630
4. Add the two like fractions:
   1260/630 + 84/630 = 1260 + 84/630 = 1344/630
5. 1344/630 simplified gives 32/15
6. So, 42/21 + 12/90 = 32/15
   In mixed form: 22/15

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