Super Brain - Sieu tri tue

Do you know a 9-year-old Japenese girl wins a girl in China in a mental calculation competition called Super Brain?
Her ability of calculation is nearly as fast as computer’s.
Do you want to try playing Superbrain game?
➤ Super Brain is a mathematical game. It not only helps to increase ability of calculation but also to become smart.
➤ Super Brain includes 3 levels:
❀ Level 1: a row of numbers includes 6 to 12 numbers.
Each number appears in 3 to 6 second (due to your choice).
You have to calculate mentally the sum of all numbers ( maybe negative number, due to your choice).
Then, you have 5 second to choose a correct answer.
❀ Level 2 is similar to level 1 but you have to calculate mentally two rows of number instead of one.
❀ Level 3: in two level above, you only calculate the sum, in level 3, you need to calculate both product and quotient of two numbers and choose answer in seven second.