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Regrouping whole numbers
Regrouping-whole-numbers 256
Description
Exercise Name: Regrouping whole numbers
Math Missions: 5th grade (U.S.) Math Mission, 6th grade (U.S.) Math Mission, Pre-algebra Math Mission
Types of Problems: 2

The Regrouping whole numbers exercise appears under the 5th grade (U.S.) Math Mission, 6th grade (U.S.) Math Mission and Pre-algebra Math Mission. This exercise introduces the concept of regrouping number to assist with borrowing.

Types of Problems[]

There re two types of problems in this exercise:

  1. Reorganize: This problem provides a number broken down by place value in the standard way, and a second break down in a non-standard way. The user is asked to fill in the missing value to ensure both representations are correct.
    Rwn1

    Reorganize

  2. Fill chart: This problem starts with a given number and a chart that breaks down the number into it's place value pieces. The user is asked to fill in the chart with what ends up being an exhaustive list of the possibilities for those units.
    Rwn2

    Fill chart

Strategies[]

This exercise is medium to get accuracy badges because the movements in the number are simple, although a couple might need to be read carefully. The speed badges are easy because the patterns are predictable and once users figure them out they can be performed rapidly.

  1. On Reorganize the place user moves to sometimes had a zero before, so user need to read the units carefully.
  2. On Reorganize the number user will put in the slot is always ten more than value of the number to the right of the spot users are in.
  3. On Fill chart the left column always decreases by one, and the right column always increases by ten.