Grade 2 Bar Models: Part-Whole Bar Models

Worked examples

Real problems from the practice worksheets, solved one step at a time.

1. Example 1

   Lisa has 11 red pencils and 14 blue pencils. How many pencils does Lisa have in all?

   1. Draw one bar for all of Lisa's pencils, split into two parts: 11 red and 14 blue.
   2. We know both parts and want the whole, so add the parts. 11 + 14: add the tens, then the ones. 11 + 10 = 21, then 21 + 4 = 25.
   3. Lisa has 25 pencils in all.

   Answer: 25

2. Example 2

   Sam has 12 red balloons and 12 blue balloons. How many balloons does Sam have in all?

   1. Draw one bar for all of Sam's balloons, split into two parts: 12 red and 12 blue.
   2. We know both parts and want the whole, so add the parts. 12 + 12: add the tens, then the ones. 12 + 10 = 22, then 22 + 2 = 24.
   3. Sam has 24 balloons in all.

   Answer: 24

3. Example 3

   Emma has 10 red crayons and 12 blue crayons. How many crayons does Emma have in all?

   1. Draw one bar for all of Emma's crayons, split into two parts: 10 red and 12 blue.
   2. We know both parts and want the whole, so add the parts. 10 + 12: add the tens, then the ones. 10 + 10 = 20, then 20 + 2 = 22.
   3. Emma has 22 crayons in all.

   Answer: 22