$24\ +\ 0\ =\ 24$  

 $\left(12+4\right)\ +\ 6\ =\ 22$  
 $12\ +\ \left(4+6\right)\ =\ 22$  

 $15\ +\ 20\ =\ 35$  

 $20\ +\ 15\ =\ 35$  

 $10\ +\ \left(3+15\right)\ =\ 28$  
 $\left(10+3\right)\ +\ 15\ =\ 28$  

 $0\ +\ 100\ =\ 100$  

 $\left(9\ +\ 18\right)\ +\ 12\ =\ 39$  

 $68\ +\ 0\ =\ 68$  

 $45\ +\ 15\ =\ 60$  

 $\left(22\ +\ 8\right)\ +\ 16\ =\ 46$  
 $22\ +\ \left(8+16\right)\ =\ 46$  

What are the missing addends?

 $10\ +\ \left(\ \ \ \ \right)\ =\ 26$  
 $16\ +\ \left(\ \ \ \ \right)\ \ =\ 26$  

What is the missing addend?

 $56\ +\ \left(\ \ \ \right)\ =\ 56$  

Find the sum.

 $\left(1+5\right)\ +\ 10\ =$  

Find the sum.

 $125\ +\ 0\ =\$  

What is the missing addend?

 $\left(12\ +\ 7\right)\ +\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ =\ 25$   $\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ +\ \left(7+6\right)\ \ =\ 25$