There are three on-off switches on a control panel A, B, and C. They have to be changed from the initial setting to a second setting according to the following conditions:
Answer: see the answer
Explanation
There are three on-off switches on a control panel A, B, and C. They have to be changed from the initial setting to a second setting according to the following conditions:
- In case switches A and B are the only switches on in the initial setting, then turn on switch C.
- In case all three switches are on the initial setting, then turn off the switch C.
- For any other initial setting, turn on all switches that are off and turn off all switches, if any, that are on.
Question:
In case all three switches are on in the second setting, which among the following could be the initial setting?
A) A on, B on, C on.
B) A on, B on, C off.
C) A on, B off, C on.
D) A on, B off, C off.
E) A off, B on, C off.
