Grade 4 - Progress in Mathematics

Update your skills. See pages 25 and 26.

240 Chapter 7

Pictographs

7-1

Kai made a tally of the number

of dogs in each category

in the dog show.

Then Kai organized his data

in a pictograph.

To make a pictograph:

List each category.

If necessary, round the data

to nearby numbers.

36 35 39 40

Choose a picture or symbol

that can represent the

number in each category.

Choose a key.

Let each 10 dogs.

Draw pictures to represent

the number in each category.

Label the pictograph. Write the title and the key.

Category Tally

Sporting

Terriers

Working

Hounds

To y

Nonsporting

Dogs in Dog Show

Sporting

Terriers

Working

Hounds

To y

Nonsporting

Key: Each 10 dogs.

Each  5 dogs.

About how many of the dogs in

the show were sporting dogs?

To find about how many, use

the key in the graph:

What is the median number of dogs?

To find the median, arrange

the actual data in order:

5, 10, 20, 30, 36, 39

The median of a set of data that has

an even number of items is the

average of the two middle numbers:

20  30  50 50  2  25

The median is 25.

10  10  10  5  35

About 35 dogs were

sporting dogs.

Dogs in Dog Show

5 5 5 5 5 5 5 1

5 5 5 5

5 5 5 5 5 5 5 1111

5 5 5 5 5 5

5

5 5

Find the median of 10, 36, 39, 5, 20, 30.

the numbers in order:

The median of a set of numbers that

has an even number of items is the

8204-6_SE4_ReprintCorrex.indd 240 9/30/10 2:46 PM