Reading Bar Graphs

Show your work for each problem.

1.
A bar graph shows favorite colors. The bar for "Blue" reaches 15 on the scale. What does this tell us?
1. a)15 people chose blue
2. b)Blue costs 15 dollars
3. c)There are 15 colors total
4. d)Blue is the 15th color
Answer: 15 people chose blue
In a bar graph, the height of each bar shows the value (count) for that category. Since the Blue bar reaches 15, it means 15 people chose blue as their favorite color.
2.
A bar graph shows pets owned by students. The Dog bar reaches 18 on the scale. How many students have dogs?
Answer: 18
The Dog bar reaches 18 on the scale, which means 18 students have dogs as pets.
3.
In a bar graph, what does the vertical axis usually show?
1. a)The title
2. b)The categories
3. c)The colors
4. d)The numbers/values
Answer: The numbers/values
The vertical axis (going up) shows the numbers or values. This is the scale that helps you read how tall each bar is. The horizontal axis shows the categories being compared.
4.
A bar graph shows apples sold each day: Monday (12), Tuesday (8). How many more apples were sold on Monday than Tuesday?
Answer: 4
1. What is the value for Monday? 12
2. What is the value for Tuesday? 8
3. To find how many more, subtract: 4
5.
A bar graph has a scale that goes: 0, 5, 10, 15, 20. What is the interval of this scale?
1. a)10
2. b)1
3. c)5
4. d)20
Answer: 5
The interval is the amount between each mark on the scale. From 0 to 5 is 5, from 5 to 10 is 5, etc. The scale goes by 5s, so the interval is 5.
6.
A bar graph shows books read: Anna (9), Ben (6), Carla (12), Dan (3). What is the total number of books read by all students?
Answer: 30
Add all the values: books total.
7.
A bar graph shows favorite sports: Soccer (20), Basketball (15), Tennis (10), Swimming (25). Which sport is the most popular and which is the least popular?
Answer: Swimming, Tennis
1. Which bar is the tallest (highest value)? Swimming
2. What is the value of the tallest bar? 25
3. Which bar is the shortest (lowest value)? Tennis
4. What is the value of the shortest bar? 10
8.
A scale goes: 0, 10, 20, 30, 40. A bar stops halfway between 20 and 30. What value does this bar represent?
1. a)25
2. b)22
3. c)27
4. d)35
Answer: 25
Halfway between 20 and 30 is 25. You can calculate it: , or just add half of the interval (10) to 20: .
9.
A bar graph shows ice cream sales: Chocolate (35), Vanilla (28), Strawberry (17). How many more scoops of chocolate were sold than strawberry?
Answer: 18
1. What is the value for Chocolate? 35
2. What is the value for Strawberry? 17
3. Calculate the difference: 18
10.
A bar graph shows hours spent on hobbies: Reading (4), Gaming (7), Sports (5), Art (3). How many hours were spent on hobbies in total?
Answer: 19
Add all the values: hours total.
11.
A bar graph shows rainfall in mm: January (45), February (30), March (60), April (75). What is the average (mean) rainfall for these four months?
Answer: 52.5
1. First, find the total of all values: 210
2. How many months are there? 4
3. Divide the total by the number of months: 52.5
12.
A bar graph shows test scores with a scale that starts at 60 (not 0). The bars show: Student A reaches 85, Student B reaches 75. What is the ACTUAL difference in their scores?
1. a)25
2. b)10
3. c)20
4. d)15
Answer: 10
Even though the scale starts at 60, the actual scores are 85 and 75. The difference is points. Be careful with graphs that don't start at zero - look at the actual values on the scale!
13.
A bar graph shows votes for class president: Emma (42), Noah (38), Olivia (35), Liam (25). How many more votes did Emma and Noah together get than Olivia and Liam together?
Answer: 20
Emma + Noah = votes. Olivia + Liam = votes. Difference: more votes.
14.
A bar graph shows weekly savings: Week 1 (8 euros), Week 2 (12 euros), Week 3 (5 euros), Week 4 (15 euros). If the goal is to save 50 euros in 5 weeks, how much must be saved in Week 5?
Answer: 10
1. What is the total saved so far (Weeks 1-4)? 40
2. What is the savings goal? 50
3. How much more is needed? 10
15.
A bar graph shows visitors to a museum each day. The tallest bar is twice as high as the shortest bar. If the shortest bar shows 45 visitors, how many visitors does the tallest bar show?
1. a)90
2. b)135
3. c)22
4. d)47
Answer: 90
If the tallest bar is twice as high as the shortest (45 visitors), then the tallest bar shows visitors.