Pictograms Questions and Answers

1.What is a pictogram?

A pictogram is a chart that uses pictures or symbols to represent data. Every pictogram has a key that shows the value of each symbol or picture. A pictogram design can be constructed using a table with two columns. In the first column is the name of the group, and the second column features the pictures.

The pictogram below shows information about the favourite subjects of some students in a class.

The first column in the above pictogram shows the list of subjects, while the second column shows the number of students who like the particular subject, using the circle symbol. According to the key in the pictogram, each circle represents four students. Which means the each half-circle in the pictogram represents 2 students.

1.1 How to Read and Interpret pictograms?

Steps:

1. Select the required row/rows.
2. To find the number of items in the selected row/rows, multiply the number of symbols in the row selected by the value of each symbol.
3. Perform the required calculation.

Let us now use the above steps and interpret the pictograms using a few examples.

1.2 Solved Examples

Example 1: The pictogram below gives information about the types of ice creams sold in an ice cream parlour on a day.

a) How many vanilla ice creams were sold?

b) How many more strawberry ice-creams were sold than chocolate ice-creams?

Solution:

a) Step 1: Selecting the row

Row: Vanilla

Step 2: Finding number of ice creams sold

Number of symbols in row vanilla = 5 1⁄2

Number of vanilla ice-creams sold = 5 1⁄2 × 4

= (5 × 4) + (1⁄2 × 4)

= 20 + 2

= 22

Hence, 22 vanilla ice-creams were sold.

b) Step 1: Selecting the rows:

Rows: Chocolate, Strawberry

Step 2: Finding number of ice-creams sold

Number of symbols in row chocolate = 3

Number of vanilla ice-creams sold = 3 × 4 = 12

Number of symbols in row strawberry =  4 1⁄2

Number of vanilla ice-creams sold = 4 1⁄2 × 4

= (4 × 4) + (1⁄2 × 4)

= 16 + 2

= 18

Step 3: Perform the required calculation:

18 - 12 = 6

Hence, 6 more more strawberry ice-creams were sold than chocolate ice-creams.

Example 2: The pictogram below shows the number of people visiting the park in the early mornings on weekdays.

Work out the total number of people who visited the park on weekdays.

Solution:

Step 1: Selecting the rows:

Rows: Monday, Tuesday, Wednesday, Thursday, Friday

Step 2: Finding the number of people

Number of symbols in row Monday = 5

Number of people visiting the park on Monday = 5 × 10 = 50

Number of symbols in row Tuesday = 5 1⁄2

Number of people visiting the park on Tuesday  = 5 1⁄2 × 4 = (5 × 10) + (1⁄2 × 10)

= 50 + 5 = 55

Number of symbols in row Wednesday = 7

Number of people visiting the park on Wednesday = 7 × 10 = 70

Number of symbols in row Thursday = 3

Number of people visiting the park on Thursday = 3 × 10 = 30

Number of symbols in row Friday = 5 1⁄2

Number of people visiting the park on Friday  = 4 1⁄2 × 4 = (4 × 10) + (1⁄2 × 10)

= 40 + 5 = 45

Total number of people visited the park on weekdays = 50 + 55 + 70 + 30 + 45

= 250

1. Tally Charts

Tally Charts are one of the different ways of collecting, recording, organizing and interpreting data. A tally chart is a simple way of recording data and counting the amount of something (frequency). Each occurrence is shown by a tally mark and every fifth tally is drawn diagonally. The tallies can then be counted to give the frequency. For example: 25 pupils were asked about their favourite type of movie.

The advantage of using a tally chart is that it can be immediately clear which item(s) occurs the most/least frequently and can be helpful when analyzing data.  The tally makes it easy to see the most popular type of movie is horror and the least popular movie type is comedy.

Other graphs/charts (such as bar charts, pie charts and pictograms) can be produced from tally charts.

1.1. Example of Tally Charts

Example: 

Mac throws the die 30 times. He put these results:

3  4  1  6  3  4  5  1  4  4  5  6  3  1  4  1  5  1  6  3  1  5  4  1  6  3  5  6  1  4

Form a table and complete the tally chart and workout the frequency (how many times he got each number) 

We see score one is repeated 8 times which is represented by 8 tally marks in an easy method. Similarly other scores. And the Frequency column adds up to 30.

Example:

Jack has a dodgy dice. He rolls it 30 times and records the results in a tally chart. Fill in the last column of the chart.

Solution:

The frequency table shows 2 + 4 + 5 + 6 + 3 + x = 30

 Number of times the dice lands on x = 30 - (2 + 4 + 5 + 6 + 3)

                                                            = 30-20

                                                            = 10

2. Pictogram

A pictogram is a chart that uses pictures or symbols to represent data. To read pictograms carefully one should understand what the symbols mean. Each picture in the pictogram represents a physical object.

All pictograms should have a key. A key shows you what each symbol represents. A pictograph design can be constructed using a table with two columns. In the first column is the name of the group, and the second column features the pictures.

For example: Below is a pictogram showing the number of doughnuts eaten by four friends in the past month.

Here, each picture represents 4 doughnuts and so we can see that Adam ate 16 doughnuts, Eve ate 10 doughnuts, Chris ate 9 doughnuts, etc.

Hence Number of doughnuts ate by Adam = 4 × 4 = 16

2.1 Examples on Pictogram:

Example: 

Mac drew a pictogram to show information about the drinks sold from a vending machine in the afternoon

Mac knew that 80 drinks were sold in total that afternoon.

How many drinks of Orange Fizz were sold that afternoon?.

The key for the pictogram is incomplete.