Answer:
The answer is %2,4
Step-by-step explanation:
Residents can press on 10 different button choice when they enters the elevator. Number of components for the sample space for the event is
[tex]10*10*10=1000[/tex]
There are 8 different possibilities that 3 consecutive buttons are pressed those are:
-1,2,3
-2,3,4
-3,4,5
-4,5,6
-5,6,7
-6,7,8
-7,8,9
-8,9,10
When the pressing order doesn't matter, those buttons can be pressed 3 different ways for each possibility.
[tex]8*3=24[/tex]
The probability is:
[tex]24/1000=0.024[/tex]