Khan Academy Wiki

The Equation practice: summing integers exercise appears under the 8th grade (U.S.) Math Mission, Algebra basics Math Mission, Mathematics I Math Mission, Algebra I Math Mission and Mathematics II Math Mission. This exercise uses lists of consecutive numbers to set up word problems.

Types of Problems[]

There is one type of problem in this exercise:

Equation practice

Find the number

  1. Find a particular number in a list: This problem asks a word problem about a collection of integers. The user is asked to find the specified number and give the answer in the space provided.

Strategies[]

There are some techniques that can be implemented to increase speed and efficiency, but being able to use variables well would be important when approaching this exercise in the standard way.

  1. When integers are consecutive, the median of the list is the average (arithmetic mean) of the list. Therefore, since the numbers are in a consecutive arithmetical order, find the average, and from that information the number it asks for can be found without setting up equations.

Real-life applications[]

  1. Knowledge of algebra is essential for higher math levels like trigonometry and calculus. Algebra also has countless applications in the real world.
  2. This problem type is common on standardized tests, including the SAT.
  3. Computers are also equation solvers. Computers were originally invented to solve equations over and over again instead of humans doing the calculations.