SOLUTION: If a divided by 4 leaves a remainder of 2 and b divided by 4 leaves a remainder of 3, then when a + b is divided by 4, the remainder is A. 0 B. 1 C. 2 D. 3 E. 4

Let all letters represent non-negative integers with 

If  divided by  gives quotient  and remainder , then 

Conversely, if  and , then  divided by 
gives quotient  and remainder . 

Suppose  divided by  gives quotient  and 
suppose  divided by  gives quotient , then



Adding the two equations,



Write  as 





By the converse above,  divided by  gives quotient
 and remainder .

That's choice b.

Edwin