SME
Grade 3 Math · Measurement & Data
Scaled picture and bar graphs
Use this for “How many pets are there in all?” on a bar graph whose scale counts by 5s.
Chart
Total: 70
Dogs and cats, difference: 10
This is an example. Type your own values to start a new problem.
Each line stands for
example
Dogs
example
Cats
example
Fish
example
Birds
example
Total
calculated
Dogs and cats, difference
calculated
Formulas
25 + 15 + 10 + 20 = 70
Dogs + cats + fish + birds = total
25 and 15 are 10 apart
Dogs and cats, difference = the taller bar − the shorter bar
Assumptions
•
Read the scale: each line is that many more. A bar between two lines is between those numbers.
•
To compare, subtract the shorter bar from the taller one.
•
The total is all the bars added.
Step-by-step
WE KNOW
Each line stands for: 5
Dogs: 25
Cats: 15
Fish: 10
Birds: 20
FIND
total, dogs and cats, difference
Step 1 · Find total
25 + 15 + 10 + 20 = ?
Dogs + cats + fish + birds = total
Add all the bars.
1
2
5
+
1
5
+
1
0
+
2
0
7
0
Total = 70
Step 2 · Find dogs and cats, difference
25 and 15 are ? apart
Dogs and cats, difference = the taller bar − the shorter bar
Subtract the shorter bar from the taller bar.
Dogs and cats, difference = 25 − 15
25 − 10 = 15
15 − 5 = 10
Dogs and cats, difference = 10 (more dogs)
Check
Put the numbers back in. Both sides should match.
25 + 15 + 10 + 20 = 70 ✓
25 and 15 are 10 apart ✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.