Addition brain training play online

This is a brain training game that you tap some of the 8 numbers and make the sum of them the same as the target number.
The score is determined by how many correct answers you get in 30 seconds.
You can turn off the sound by unchecking "Sound" in the menu item.
Studies have shown that brain training by simple calculation remains highly effective in activating the brain even after getting used to the same thing over and over again.
It seems that brain training with a time limit makes the brain more active by being conscious of answering quickly.