Maths topic

graphs and data

Data is information collected to answer a question. Graphs help us show the data so it can be read and compared.

Practise graphs Make a graph Back to topics

the big idea

Graphs and data help us answer questions. First we ask a clear question, then collect information, show it neatly and compare what it tells us.

question Which fruit is most popular?
collect count each vote
show table, tally or graph
compare most, least, total

show the same data

Choose a display and see how the same fruit votes can be shown in different ways.

Favourite fruit
apples 8
bananas 5
berries 6
oranges 3

bar graph

questionWhich fruit is most popular? total22 votes compareapples have 5 more than oranges rememberBars make it easy to compare counts.
display

data starts with a question

Data is information collected to answer a question.

  • A good data question tells us what information to collect.
  • Each answer can fit into a category.
  • Counting each category helps us compare the results.
Which fruit is most popular?
apples bananas berries oranges

Each answer belongs in one category.

tables and tallies organise counts

Tables line up categories and counts. Tallies are marks that help count quickly.

  • A table keeps each category in its own row.
  • Tallies can be grouped in fives to count faster.
  • The count tells how many pieces of data are in that category.
Favourite fruit
fruit tally
apples
bananas
berries
oranges

bar graphs compare amounts

A bar graph uses bars to show and compare data.

  • Each bar shows one category.
  • The bar length or height shows the count.
  • A graph needs a title, category labels and a scale.
Favourite fruit
apples 8
bananas 5
berries 6
oranges 3

The longest bar has the greatest count.

pictographs use pictures

A pictograph uses symbols or pictures to show data.

  • Each picture stands for a number.
  • On this page, one picture stands for one vote.
  • The key tells what each picture means.
Favourite fruit

key: 1 picture = 1 vote

apples AAAAAAAA
bananas BBBBB
berries RRRRRR
oranges OOO

read and compare the graph

Graphs help answer questions about most, least, total and difference.

  • Most means the category with the greatest count.
  • Least means the category with the smallest count.
  • The total is all the counts added together.
  • The difference tells how many more one category has than another.
most apples 8 votes
least oranges 3 votes
total 22 votes altogether
difference 5 more apples

line graphs show change over time

A line graph can show how a measurement changes over time.

  • A line graph is useful when data is collected in order, such as over days or months.
  • Points show the data values.
  • The line helps show whether the values go up, down or stay about the same.
Mon 3 Tue 4 Wed 6 Thu 5 Fri 8 Plant height over time

The points go up overall across the week.

data words

These words help us collect, show and read data.

1 data information

information collected to answer a question

2 category group

one answer group in the data

3 tally counting marks

marks used to count data quickly

4 graph data picture

a display that helps data be read and compared

5 bar graph bars

a graph that uses bars to show counts

6 pictograph pictures

a graph that uses pictures or symbols

7 scale counting steps

the numbers used to read a graph

graphs and data facts

fact Data answers a question
fact Tallies can be grouped in fives
fact Bar graphs use bars
fact Pictographs use pictures
fact Graphs can show most and least
fact Line graphs can show change over time

real world examples

class votes finding the most popular fruit, sport or book
weather recording temperature across a week
sport comparing goals, points or times
surveys collecting answers from classmates
science measuring plant growth over days
school checking attendance or library borrowing

quick graphs and data quiz

Try a few graph and data ideas. This quiz only asks about ideas shown on this page.

What is data?

Which display uses tally marks?

Which graph uses bars?

In the fruit votes shown here, which fruit has the most votes?

What can a line graph show?