Answer: 32 buttons
Explanation:
Matt has 11 white buttons.
Matt has 9 fewer brown buttons than white buttons. This means he has (11 -9) = 2 brown buttons
Matt has 17 more grey buttons than brown buttons. This means that he has (2 + 17) = 19 grey buttons.
The total number of buttons that Matt has will be;
= 11 white + 2 brown + 19 grey
= 32 buttons