Khan Academy Wiki
Subtract within 10
Takeapart2
Description
Exercise Name: Subtract within 10
Math Missions: Early math Math Mission
Types of Problems: 1

The Subtract within 10 exercise appears under the Early math Math Mission. This exercise practices the order of the amount being subtracted and where it is being subtracted from. It continues strengthening a set theoretic model of arithmetic as an operation on objects.

Types of problems[]

There is one type of problem that show up in this exercise:

  1. Take away some from group: This problem describes a situation involving take away and the user is asked to correctly type in the answer to the subtraction problem in context.
    Takeapart2

    Subtract the amount

Strategies[]

Knowledge of subtracting small numbers is important for this exercise.

  1. These problems are straightforward making them easy to attain accuracy badges. However, due to the multiple things that are needed on the first problem type getting speed badges should be viewed as medium difficulty.
  2. On the first problem type, the number of objects in the bottom picture (if matched correctly) is the final answer to the subtraction problem since it represents how many are left in the word problem.
  3. This could easily change in the future, but it appears that 2 is the correct answer to all of the second type of problems. This is probably an accident at this time and may change in the future.

Real-Life Applications[]

  1. Subtraction can be used by businesses to see how much money they make minus the money they spent for profit.
  2. Subtraction is a major fundamental for higher math levels like algebra, calculus, and more.