[SOLVED] Multitouch input to Entry

I have couple number buttons, and when I click some button, button inserts number to text in memory “Entry” but when I click another button, numbers in Entry are replaced with new button number. I would like to make like multitouch so if I click two times 5 to get 55, because now it’s works like when I press second time 5 I still get just 5. It is multiplication game I make for my kid, so that the kid as sum can insert result by clicking buttons.

In the mean time I could to solve that by myself…No further assistance needed!