Cogito
Grade 3 Math · Chapter 6 · Lesson 5
Line Plots With Fractions
Plotting measurements that land between numbers.
10 problems · about 13 minutes · 3.MD.B.4
What this lesson teaches
The child builds a line plot of measurement data with halves and fourths on the scale.
- A line plot puts one mark above the measured length.
- The scale can include halves and fourths.
- The tallest stack is the most common measurement.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
3 problemsReview — Measuring to Halves and Fourths: How many fourths make three quarters?
Answer 3
Why Three fourths is three of the small marks.
Review — Two-Step Graph Problems: Bars of 40, 15 and 5. How many more is the first than the other two together?
Answer 20
Why 40 − 20 = 20.
Review — Scaled Bar Graphs: A scale of 5, bar at the seventh mark. What value?
Answer 35
Why The bar shows 35.
Warm Up
Straightforward practice. Get the method working first.
3 problemsStacks of 2, 3, 4 and 1. How many measurements in all?
Answer 10
Why 2 + 3 + 4 + 1 = 10.
What does the tallest stack tell you?
Answer The most common measurement.
Why Height counts measurements; position gives the length.
Stacks of 1, 4, 5, 3, 0 and 2. How many measurements in all?
Answer 15
Why Add every stack.
Build It Up
The same ideas with more to keep track of.
1 problem5 marks at 4 in and 3 at 5 in. How many more measured 4?
Answer 2
Why 5 − 3.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
3 problemsA column with no marks means what?
Answer Nothing measured that length.
Why The number is still on the scale.
Reading the Plot: A plot has 4 marks at 3 in and 5 at 4 in. How many pencils were 3 or 4 inches?
Answer 9 pencils
Why 4 + 5 = 9 pencils.
The Most Common: Stacks of 1, 4, 5, 3, 0 and 2. What is the tallest stack?
Answer 5 marks
Why The tallest stack has 5 marks.