[?] + [3] = 10

Try this easy calculation!

This app is a number puzzle that matches the sum of numbers from 2x1 to 9x9 grid to 10.
From children to adults, you can have fun brain training.

If you solve it with great skill, you get a big carrot as a reward. Increase your mental arithmetic and gather a lot of carrots to show off.

2x1, 3x1, 4x1, 5x1, 2x2, 3x3 : Let the sum of all the numbers be multiples of 10.
5x5 : Let the sum of the numbers of horizontal and vertical lines be multiples of 10.
6x6, 9x9 : Let the sum of horizontal, vertical and square numbers to be multiples of 10.