Answers

Add 21/45 and 12/36

21/45 + 12/36 is 4/5.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 36 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 45 × 4 = 180,
   21/45 = 21 × 4/45 × 4 = 84/180
3. Likewise, for the 2nd fraction, since 36 × 5 = 180,
   12/36 = 12 × 5/36 × 5 = 60/180
4. Add the two like fractions:
   84/180 + 60/180 = 84 + 60/180 = 144/180
5. 144/180 simplified gives 4/5
6. So, 21/45 + 12/36 = 4/5

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