Percentiles and cumulative frequency graphs - Quiz

If I tell you that you scored at the 55th percentile on your final exam, you would know:

• 55% of the class scored the same or worse than you did

• You earned a 55% on the exam

• You failed the exam

• 45% of the class scored worse than you did

The 75th percentile is also know as the

• median
• third quartile
• 1st quartile`
• interquartile range

The Median is also referred to as

• the 25th Percentile

• the 50th Percentile

• the 75th Percentile

• the 100th Percentile

Connor does a survey on how much money 100 people spend over the Christmas period.

The results have been plotted on a cumulative frequency diagram.

Estimate the value of the 30th percentile.

• £ 24

• £ 20

• £ 30

• £ 28

Connor does a survey on how much money 100 people spend over the Christmas period.

The results have been plotted on a cumulative frequency diagram.

Estimate the interquartile range.

• £ 23

• £ 28

• £ 40

• £ 26

Connor does a survey on how much money 100 people spend over the Christmas period.

The results have been plotted on a cumulative frequency diagram.

Use the cumulative frequency diagram to estimate the number of people who spent over £50 during the Christmas period. write your answer as a figure only.

Graham collects data on the ages of people in his village.

(Level 6)

He has summarised the information in the frequency table below. He then plots his information on a cumulative frequency diagram as shown.

Identify the mistakes Graham has made when plotting his cumulative frequency diagram. choose all that apply.

• Graham has used straight lines to join the points rather than a smooth curve.

• Graham only plotted the cumulative frequency up to 90 instead of 100.

• Graham's graph should started from (0,10) instead of (0,0)

• Grahams scale on the x-axis is incorrect.

Eve collects information on the household spending per day for 100 families. The information has been summarised in the cumulative frequency diagram below.

How many families spend greater than £25, but lower than £45, per day?

• 52 families

• 32 families

• 84 families

• 41 families

Eve collects information on the household spending per day for 100 families. The information has been summarised in the cumulative frequency diagram below.

The 70th percentile is £ ____________

Write you answer as a figure.

A TV company surveyed 88 of its employees to find out how much time they spend travelling to work on a given day. The results of the survey are shown in the following cumulative frequency diagram.

Estimate the 50th Percentile

• 42 minutes

• 34 minutes

• 29 minutes

• 49 minutes