Statistics: Reading and Choosing Graphs

Bar graphs, histograms, line graphs and circle graphs: reading them, choosing between them, and spotting when one is used to push a point of view.

11 questions, free, marked as you go with a worked explanation on every one.

What this covers

A circle graph shows how a worker's monthly budget is divided. Housing takes up 35% of the budget. What is the angle of the housing sector, in degrees?
A line graph shows a company's sales rising steadily from $40 000 in 2020 to $64 000 in 2024. Assuming the trend is linear, estimate the sales in 2022, in dollars.
Using that same steady trend of sales rising from $40 000 in 2020 to $64 000 in 2024, estimate the sales in 2026, in dollars.
A shop wants to display how a single product's monthly sales have changed over three years. Which graph type is most suitable?
A company's bar graph shows profits rising sharply, but the vertical axis starts at $95 000 instead of $0. What is the effect?
What distinguishes a histogram from a bar graph?
A histogram of daily service calls shows 12 days with 0 to 4 calls, 18 days with 5 to 9, 25 days with 10 to 14, 15 days with 15 to 19 and 10 days with 20 to 24. On how many days were there 10 or more calls?
A circle graph of 720 survey responses shows that the 'strongly agree' sector measures 90°. How many respondents chose 'strongly agree'?
A survey wants to show what fraction of a town's budget goes to each department. Which graph type is most suitable?
Use the bar graph below, showing monthly rainfall in four cities. Which city had the least rainfall?
A line graph shows a company's profit dipping sharply for one month, then recovering. Which best describes how to read that dip?