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4th grade math · Unit 9: Measurement and time

Elapsed time on a number line

What this lesson shows

9:40 to 11:15 in jumps to the next hour, across noon too.

The worked example

The lesson works this one step by step: 9:40 a.m. to 11:15 a.m. Then your kid tries one like it on paper.

The steps

  1. Jump to the next hour
  2. Jump whole hours
  3. Jump the minutes left
  4. Add the jumps

Helping at home

Draw an open number line with the start and end times. Jump to the next whole hour first, then jump whole hours, then the minutes left. Add the minute jumps, and remember that 60 minutes make 1 hour. After 12:00 noon the clock starts again at 1.

If your kid gets stuck

Jump to the next whole hour first.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

Standards

  • Common Core 4.MD.A.2
    Use the four operations to solve word problems involving distances, intervals of time, liquid volumes, masses of objects, and money, including problems involving simple fractions or decimals, and problems that require expressing measurements given in a larger unit in terms of a smaller unit. Represent measurement quantities using diagrams such as number line diagrams that feature a measurement scale.
Matches standards in 50 statesSee each state's code

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