Understanding fractions
Make a line plot to display a data set of measurements in fractions of a unit (1/2, 1/4, 1/8); use operations on fractions to solve problems involving data in line plots (e.g. redistribute total equally)
What a learner can do afterwards
- Create a line plot showing lengths measured to the nearest 1/8 inch
- Use the line plot to find the total of all measurements by adding fractions
- Solve: 'If the total liquid were redistributed equally among all beakers, how much would each have?'
The lesson
You already know how to read a line plot and how to add fractions with different denominators. Now put those two skills together. A line plot can show measurements like pencil lengths in fractions of an inch, and once the plot is made, you can add up the numbers on it to answer real questions.
To find the total length of all the pencils, add each length once for every pencil at that mark: 1/4 + 1/4 + 3/8 + 1/2 + 1/2 + 1/2 + 5/8 + 5/8. Rewrite everything in eighths first, then add. The total comes out to 3 5/8 inches.
When you add fractions from a line plot, find a common denominator first. If every mark on the plot is already in eighths, that part is done for you.
A line plot can also help you share a total fairly. Four beakers hold 1/2, 1/2, 1/4, and 1/4 cup of water. Poured together, that is 1 1/2 cups. Split evenly among the 4 beakers, each one gets 3/8 cup.
Read how many measurements sit at each mark on the plot, then add those fractions to find totals or split amounts equally.
Watch it
Where it sits
This opens up
Nothing builds on it yet.
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.