4.2: What's the Weight
Look at the picture below. Can you figure out the weight of the blue block? Can you figure out the weight of the red block? In this concept, we will learn how to find the weights of individual blocks given information about the weights of multiples or combinations of blocks.
Guidance
In order to solve the problem above, use the problem solving steps.
- Start by describing what information is given.
- Then, identify what your job is. In these problems, your job will be to figure out the weight of each individual block.
- Next, make a plan for how you will solve. In these problems, find the weight of the block using the scale that shows only one type of block first.
- Then, solve the problem.
- Finally, check your solution. Make sure that your solution causes each scale to have the correct weight.
Example A
Figure out the weight of each block.
Solution:
We can use the problem solving steps to help us.
Example B
Solution:
We can use the problem solving steps to help us.
Example C
Figure out the weight of each block.
Solution:
We can use the problem solving steps to help us.
Concept Problem Revisited
We can use the problem solving steps to help us solve this problem.
Vocabulary
In math, an unknown is a letter that stands for a number that we do not yet know the value of. In this concept, when you figured out the value of the individual blocks you were solving for unknowns.
Guided Practice
For each problem, figure out the weight of each block.
1.
2.
3.
Answers:
1. Green block is 5 pounds; yellow block is 8 pounds.
2. Yellow block is 7 pounds; blue block is 2 pounds.
3. Red block is 6 pounds; green block is 1 pound.
Practice
For each problem, figure out the weight of each block.
Image Attributions
Description
Learning Objectives
Students determine the individual weights of two different blocks given information about the weights of multiples or combinations of blocks. Students use problem solving steps to help them.