## Key Concepts

- Organizing the data
- Making line plot
- Measurement data in line plot to solve problems

## Introduction

In this chapter, we will learn how to organize data, make a line plot and measure data in line plots to solve problems.

## Make line plots

- A line plot is a graph that displays data using a number line.
- Line plots are also called dot plots.

The image below is an example of a line plot.

### Organizing the data

Organizing data is bringing it together in a systematic way that makes it easier to read.

- Data can be organized using
**tallies**and**frequency tables**. - Tallies are a way of counting by drawing a short vertical line to record each item.

**Example 1:**

Following is the data of weights collected during the medical check-up of 35 students of a class:

**Step 1:** Write the weights from least to greatest.

**Step 2:** Organize data in a frequency table.

**Example 2:**

The kids in a daycare centre have the following weights. How can you organize this information?

**Step 1: **Write the weights from least to greatest.

**Step 2**: Organize the data in a frequency table.

### Making line plot

- To make a line plot, first, create a number line that includes all the values in the data.
- Place an X (or dot) above each data value on the number line.
- A value occurs more than once in a data set. Place an X over that number for each time it occurs.

**Example 1:**

The following table shows the number of ribbons of each length. Create a line plot for this data.

**Step 1:** Draw the number line using an interval of 1.

**Step 2:** Mark *x *for each value in the data set.

**Step 3:** Write the title for the line plot.

**Example 2:**

David measured the lengths of his friends’ hands. He records the measurements in the table below.

Make the line plot using David’s data.

**Solution:**

**Step 1:** Draw the number line using an interval.

**Step 2:** Mark *x* for each value in the data set.

**Step 3:** Write the title for the line plot.

### Measurement of data in line plot to solve problems

**Example 1: **

The heights of Sabrina’s dolls are shown below.

- How many dolls are taller than 22 centimetres?

- How many dolls are 24 centimetres?

- How many total dolls are there?

**Solutions:**

- 5 dolls

- 3 dolls

- 14 dolls

**Example 2:**

The line plot shows the length of sticks in inches. Use the line plot to answer the questions.

- How many sticks are 2 inches long?

- What is the length of most of the sticks?

- How many sticks are 3 inches long?

**Solution:**

- 2 sticks

- 1 inch

- 1 stick

## Exercise

1. The following data points represent the number of trick-or-treaters James had each year since he started putting pumpkins in his yard. Organize the data in a frequency table. 54, 56, 53, 54, 56, 55.

2. The following dot plot shows the daily high temperature in Key West, Florida, in April. Each dot represents a different day. How many days had a temperature of at least 16 °C?

3. Quarterback Susie has a bad attitude and often gets fined for bad sportsmanship. Below are the costs of each of the six fines assessed to her this season in thousands of dollars)

Using this data, make a plot.

4. Keta is asked to collect data for the size of shoes of students in her Class VI. Her finding is recorded in the manner shown below:

Organize the given data in a frequency table.

### Concept Map

### What have we learned

- Understanding line plots
- How to organize the data
- How to make the line plots using data
- How to solve word problems using measurement data

#### Related topics

#### Addition and Multiplication Using Counters & Bar-Diagrams

Introduction: We can find the solution to the word problem by solving it. Here, in this topic, we can use 3 methods to find the solution. 1. Add using counters 2. Use factors to get the product 3. Write equations to find the unknown. Addition Equation: 8+8+8 =? Multiplication equation: 3×8=? Example 1: Andrew has […]

Read More >>#### Dilation: Definitions, Characteristics, and Similarities

Understanding Dilation A dilation is a transformation that produces an image that is of the same shape and different sizes. Dilation that creates a larger image is called enlargement. Describing Dilation Dilation of Scale Factor 2 The following figure undergoes a dilation with a scale factor of 2 giving an image A’ (2, 4), B’ […]

Read More >>#### How to Write and Interpret Numerical Expressions?

Write numerical expressions What is the Meaning of Numerical Expression? A numerical expression is a combination of numbers and integers using basic operations such as addition, subtraction, multiplication, or division. The word PEMDAS stands for: P → Parentheses E → Exponents M → Multiplication D → Division A → Addition S → Subtraction Some examples […]

Read More >>#### System of Linear Inequalities and Equations

Introduction: Systems of Linear Inequalities: A system of linear inequalities is a set of two or more linear inequalities in the same variables. The following example illustrates this, y < x + 2…………..Inequality 1 y ≥ 2x − 1…………Inequality 2 Solution of a System of Linear Inequalities: A solution of a system of linear inequalities […]

Read More >>
Comments: