Sample Test

Often we use numbers to represent things in the real world.  Each number is just a group of those things. When we subtract, we take away things things from the group.

• Example:  

  Ο	Ο	Ο		−	Ο		=	Ø	Ø	Ø
  Ο	Ο	Ο	Ο		Ο	Ο		Ο	Ο	Ο	Ο
  7					3			4

• You can also think of subtraction as an addition problem.
• Example: The equation 7 − 3 = ?  can be rewritten to  ? + 3 = 7
• The easiest way to subtract is to stack your numbers up in rows.
• Pay attention to how the equation is written.
• 8 − 4 = ?  means the 8 is on the top and the 4 is on the bottom.
• Make sure to line them up at the ones place.
• Then subtract each column.
• Example:  

  		8
  -		4
  		4

Tip: Use a piece of lined paper sideways to keep your columns straight.