Numbers And Differences

Test your working memory and mental calculation by remembering numbers and calculating their differences.

Objective

Remember numbers as they appear one after another, then calculate and type the absolute difference between them.

How It Works

This game challenges your working memory by requiring you to remember numbers as they appear sequentially. You must maintain the previous number in memory while processing the new number, then quickly calculate the absolute difference. The challenge increases with shorter display times and faster pacing between numbers.

Step-by-step Instructions

Two numbers will appear, one after the other (each number is between 1 and 9)
When the second number appears, calculate the difference between the two numbers
Type the absolute difference (the result is always positive, never negative)
Then a new number will appear and you repeat the calculation with the new and previous numbers
Calculate the difference between this new number and the previous number you saw (not the answer you typed)
Continue calculating differences as new numbers appear
Use your numpad to enter answers, and make sure num lock is on

Skills You Develop

Working memory - ability to hold numbers in mind
Mental arithmetic and calculation
Number sequence tracking
Quick calculation under time pressure
Concentration and focus
Memory encoding and retrieval

Coaching Tips

Focus on remembering the number that just appeared, as you'll need it for the next calculation
Practice mental subtraction to calculate differences quickly
Remember that the answer is always the absolute difference between the two numbers (it is always positive)
Example: If you see 5, then 7, calculate |7 - 5| = 2. Then if 4 appears, calculate |7 - 4| = 3 (using the previous number 7, not your answer 2)
Keep your finger ready on the numpad for quick entry
Stay calm and focused - rushing can lead to calculation errors
If you forget a number, try to reconstruct it from the sequence you remember