FAST ADDITION

Sometimes, standing at the cash register of a store, you catch yourself thinking that you can't quickly calculate the cost of your purchase. When the cashier announces the verdict, you start frantically adding up the numbers in your mind, trying to figure out whether the amount was calculated correctly, whether the cashier made a mistake. You can certainly use a calculator in your mobile phone or a separate counting machine, but I doubt that many people carry one with them, and I don't want to burden store employees and customers with waiting in line. But cashiers, not often, but make mistakes! Agree that you should not lose your money in such cases. That's why you just need to be able to quickly count numbers, namely add them up. This flash game is just a counting simulator. You are invited to pick up numbers on the game table for a certain time specified by the program, the sum of which is set by the computer and shown on the screen. The game perfectly trains the speed of adding prime numbers. Points are awarded for correct answers and the speed of your calculations. You can compete with your colleagues at work or, for example, with the household and find out which of you counts better and faster. In addition, for schoolchildren, this is also a great way to improve elementary mathematics.