Drawing 40 pictures takes too long. So one picture is made to stand for several.
Step 1: Let's Learn
Read it, or press Listen and follow the words.
The graph tells you how many, in a note called the key.
Key tells you what one symbol on a graph stands for.
Read by multiplying
If one picture is 5 and a column has 4 pictures, that column is 4 × 5 = 20.
You have met this before
A dime stands for ten pennies. One symbol standing for many is the same idea.
When one picture means several
A scaled picture graph uses one symbol to stand for more than one thing — perhaps each apple picture means 5 apples. The key says so. Reading the graph without reading the key gives an answer five times too small.
Reading it is a multiplication
Six symbols with a key of 5 means 6 × 5 = 30. Scaled graphs turn data reading into a multiplication problem, which is exactly why they appear after the multiplication chapters rather than before.
Part symbols
Half a symbol means half the key value — with a key of 5, half a symbol is 2 or 3 depending on how the graph rounds. Scaled graphs work best when the data are multiples of the key, which is one reason the key is chosen carefully.
Step 2: Try It Yourself
Read the key first, then count the symbols.
Apples
Fish
Stars
Key: each symbol stands for 5.
There are 65 in all.
Fish has the most. It has 15 more than Stars.
Step 3: Watch an Example
One step at a time.
Watch Ana Read a Key
A graph shows 4 apple pictures, and the key says each one is 5.
- Step 1
She reads the key before counting anything.
Step 4: Your Turn
Practice makes it stick.
The Survey
Problem 1 of 2
Each picture stands for 10. A column has 3 pictures. How many is that?
Two Columns
Problem 2 of 2
Each picture is 5. One column has 6 pictures, another has 3. How many more in the first?
Read the Key
1 of 3
Each picture is 5. A column has 7 pictures. How many?
2 of 3
Each picture is 2. A column has 9 pictures. How many?
3 of 3
Each picture is 10 and the total is 60. How many pictures?
Step 5: Quick Check
Show what you know.
Question 1 of 2
Each picture is 5. A column has 8 pictures. How many?
Question 2 of 2
What is the first thing to read on a scaled graph?
What You Learned
- One picture can stand for several things.
- The key tells you how many.
- Count the pictures, then multiply.