on Start of Layout:
-set Text to round(random(1,10)) for the 2 number text objects. (Number1Text and Number2Text)
-set Text to choose("+","-","*","/") for the operator text box. (OperatorText)
Then on Sprite click (your action button)
-if OperatorText.text = "+" then Set AnswerText.text to int(Number1.text) + int(Number2.text)
etc.. for each operator
You need some other User button to reset the fields, so I suggest a Clear/Reset button which you can just re-execute the code in On Start of Layout.