7月22日的Add Up 10.应用程序分析

Arithmetic for the first step. You can learn to add and subtract easily and become familiar with numbers. Let's learn how to make 10 using two numbers. Add 1 to 9 is 10, 2 to 8 is 10, 3 to 7 is 10... The answer is always single-digit figure. Beat the Robo by answering the questions.