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The Factor pairs exercise appears under the 4th grade (U.S.) Math Mission, 6th grade (U.S.) Math Mission, Pre-algebra Math Mission and Mathematics I Math Mission. This exercise introduces the idea of factor pairs for composite numbers.

Types of Problems[]

There are two types of problems in this exercise:

  1. Identify pairs of factors of the number: This problem provides a number or area that is an integer. The user is asked to identify all the options from a multiple select list that are factor pairs for the number, or possible lengths and widths for the rectangle
    Fp1-too

    Identify pairs of factors of the number

  2. Find the other pair in the factor pair: This problem provides a situation where one half of a factor pair is provided. The user is expected to fill in the other half of the factor pair as appropriate.
    Fp2-too

    Find the other pair in the factor pair

Strategies[]

Being able to create a factor tree quickly can help to perform this problem well. Factor trees are also valuable for concepts like LCM and GCF which will lead into increased ability with fractions.

  1. The area of a rectangle is a product so it is a natural word problem to identify factor pairs.
  2. The Find the other pair in the factor pair problem is sometimes worded as a split into rows or columns word problem.
  3. Given one factor, division of the large number by one factor will yield the other.

Real-life Applications[]

  1. Multiplication is needed and used by mechanics for repairing cars by multiplying when they overhaul the engine, measure the pistons or just to put in a new gearbox or engine.