Convert fractional measures exactly
Name the same fractional or decimal measure in smaller units without rounding.
Explore this lesson →16 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- A fraction of a unit is still a measured amount. Its denominator tells how many equal parts make one source unit.
- Changing the unit preserves the quantity. Multiply by the number of smaller units in one source unit; the new count may still include a fraction.
- Decimal hours are fractions of an hour. Half an hour is 30 minutes; decimal digits do not stand for minutes.
Something to notice
Ask the learner to explain why one measured quantity can have two exact unit names, including a noninteger smaller-unit count. Check with a physical measuring tool where practical. Ask them to point to one whole source unit, explain each smaller-unit mark, and show why changing units leaves the measured amount unchanged.
Try it. Change it. Explain it.
Open the lesson to use its pictures and controls. In How it works, connect the picture to the idea. In Play & discover, change the quantities and notice what stays the same. In Your turn, answer questions and use the explanation to check your reasoning.
You can ask for help, draw on the thinking pad, or listen to the question and answer options. Progress distinguishes independent work from work completed with help.
Let’s try it →Curriculum connection
Grade 4 · 4.MD · US Common Core
This lesson is mapped to these standards. A completed activity is practice evidence, not a claim of mastery. Content is checked against the linked official standards and its mathematical models are tested.