Complete the following math problems:

Решение:

1. 
   

   18 + 30 = 48

   
   

   18 + 30 = 48

   
   

   18 + 30 = 48

   
   
2. 
   

   20 + 4 = 24

   
   

   20 + 4 = 24

   
   

   20 + 4 = 24

   
   
3. 
   

   14 + 7 = 21

   
   

   14 + 7 = 21

   
   

   14 + 7 = 21

   
   
4. 
   

   9 + 8 = 17

   
   

   9 + 8 = 17

   
   

   9 + 8 = 17