Zero/Sum IPA

Zero / Sum is an exciting math game for iOS where you will solve various examples. The plot of the game begins with the fact that a talented scientist has found a cure for cancer, but it is being killed by terrorists and now you, as her assistant, have to restore all the equations. Before you will be a board with numerous numbers, your task will be to place the signs in the desired order so that, as a result, the sum in the example is zero. Solve numerous examples and show all your observability and mathematical knowledge.