Arithmetic Grade Four

Lesson Thirty-one: Number Sequences

Consider the following problem: 

   14 + 8 + 8 + 8 + 8 =
There are a couple of ways we might choose to solve this problem. Here are three equally effective ways of solving this problem: 
ONE: Convert 8 + 8 + 8 + 8 into a multiplication problem.

   14 + 4 x 8 
 
   In this case, we multiply 4 x 8 and get 32. We then add 14 + 32 
   and get the answer.

TWO: Add 8 + 8 + 8 + 8.

   14 + 8 + 8 + 8 + 8 

   In this case we solve the problem 8 + 8 + 8 + 8 like this:

      8 + 8 + 8 + 8 = 
      16 + 8 + 8 =
      24 + 8 =
      32

    Once we figure out that 8 + 8 + 8 + 8 equals 32, we go on to add
    14 + 32 to get the answer.

THREE: Add from left to right in order.

    14 + 8 + 8 + 8 + 8 =
    22 + 8 + 8 + 8 =
    30 + 8 + 8 =
    38 + 8 = 
    46
In this next activity you use the first method to sequence problems.

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