This is a fantastic App designed by Mathematics Teacher.

The App teaches you how to solve Simple Equations in easy to follow steps using many teaching examples. First follow the examples and then do the exercise in your notebook. All questions are computer generated at random.

You can do these questions in your head to practice basic arithmetic. You can do the harder questions as well this will give you practice in becoming a brilliant mathematician.
Start at the beginning and progress to the next stage at your own pace. Try and show your working out as you go along. There is a test at the end, the first test is out of ten
and the second is out of 20.

All answers are positive and whole numbers for easy understanding and working out.
Good Luck.