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Multiplying and dividing decimals by powers of 10
Multiplying-and-dividing-by-powers-of-10 256
Description
Exercise Name: Multiplying and dividing decimals by powers of 10
Math Missions: 5th grade (U.S.) Math Mission
Types of Problems: 2

The Multiplying and dividing decimals by powers of 10 exercise appears under the 5th grade (U.S.) Math Mission. This exercise strengthens the knowledge that multiplying and dividing by powers of ten moves the decimal point either left or right.

Types of Problems[]

There are two types of problems in this exercise:

  1. Multiply or divide the number by powers of ten: This problem asks several questions that involve multiplying or dividing a particular number that may involve decimals by different powers of ten. The user is asked to fill in the correct answers.
    Maddbpo101

    Multiply or divide the number by powers of ten

  2. Multiply or divide the numbers by the power of ten: This problem provides a power of ten that is to be multiplied or divide against different numbers. The user is asked to provide all correct answers.
    Maddbpo102

    Multiply or divide the numbers by the power of ten

Strategies[]

Knowledge of the base ten number system and the result in this system when working with powers of ten is an advantage, but to complete the exercise all one needs is an ability to perform basic arithmetic operations.

  1. Multiplying by a power of ten moves the decimal place to the right the same number of spaces as the exponent on the power of ten.
  2. Dividing by a power of ten moves the decimal place to the left the same number of spaces as the exponent on the power of ten.

Real-life applications[]

  1. Scientific notation uses powers of ten to represent large and small quantities in a more efficient way.
  2. Powers of ten simplify comparison of numbers by order of magnitude.