Answers

Add 21/90 and 12/30

21/90 + 12/30 is 19/30.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 30 is 90
   
   Next, find the equivalent fraction of both fractional numbers with denominator 90
2. For the 1st fraction, since 90 × 1 = 90,
   21/90 = 21 × 1/90 × 1 = 21/90
3. Likewise, for the 2nd fraction, since 30 × 3 = 90,
   12/30 = 12 × 3/30 × 3 = 36/90
4. Add the two like fractions:
   21/90 + 36/90 = 21 + 36/90 = 57/90
5. 57/90 simplified gives 19/30
6. So, 21/90 + 12/30 = 19/30

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