Khan Academy Wiki
Find 1 more or 1 less than a number
One-more--one-less 256
Description
Exercise Name: Find 1 more or 1 less than a number
Math Missions: Early math Math Mission
Types of Problems: 1

The first instance of the Find 1 more or 1 less than a number exercise is under the Early math Math Mission. This exercise helps users to understand the positions of consecutive numbers. It also reinforces the idea of more and less by training the user to quickly move forward and backward among whole numbers

Count1

Types of problems[]

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

  1. Select the correct answer before or after the given number: A picture and short word problem are given. The word problem is about the picture and involves either adding one or subtracting one from the given number. The answer is chosen from three possible answer choices given below the problem.

Strategies[]

Since this problem is selecting the correct answer choice and involves small numbers it is easy to get speed and accuracy badges on this exercise.

  1. The correct answer never exceeds twenty and is never zero, so a picture with one object will have to have an answer of two and a picture with 20 objects will have to have an answer of 19.
  2. It is easier to go quickly without reading problem if the user reads then number in the problem and look at the answer choices. In most cases, only one number is adjacent to the number given in the problem so that is the solution. If the numbers above and below are among the possible answer choices, users will need to completely read the problem to see if it is more or less.

Real-life Applications[]

  1. Knowledge of adding and subtracting numbers are essential for algebra and the higher maths.
  2. The whole world evolves around numbers and counting.