We are given
arithmetic sequence: u(1)= 124, u(2)= 117, u(3)= 110, u(4)=103
so, first term is 124
u(1)= 124
now, we can find common difference
now, we can find kth term
now, we can plug values
and we get
u(k) must be negative
so,
now, we can solve for k
so, it's closest integer value is
..............Answer
Answer:
Check the explanation
Step-by-step explanation:
Since each and every one of the 4 hallways is equally likely then
Now, if he chooses H1 he escapes after 12 minutes then
If he chooses H2 then he wastes 10 minutes and then he is again in the same starting
position so he expects to escape in E(T) minutes, then
Analogously, if he chooses H3 then he wastes 40 minutes and then he is again in the same starting
position so he expects to escape in E(T) minutes, then
Therefore
So we have
Therefore he is expected to escape in 72 minutes