Respuesta :
Answer:
The ordered pair (e₁, e₂) is (6, 8).
Step-by-step explanation:
Consider the pathway attached below.
- Consider that Fred is at 1.
It is provided that Fred moves to either 0 or 2 with equal probability, i.e. 0.50.
e₁ : 1 3 5 7 ...
P (e₁) : 0.50 0.50² 0.50³ 0.50⁴ ...
The expected number of steps Fred takes to get to 0 if he is at 1 is:
[tex]e_{1}=(1\times 0.50)+(3\times 0.50^{2})+(5\times 0.50^{3})+(7\times 0.50^{4})+...\\\\[/tex]
The sum series e₁ is an AGP.
The sum of infinite AGP is:[tex]\frac{a}{1-r}+\frac{dr}{(1-r)^{2}}[/tex]
Then the value of e₁ is:
[tex]e_{1}=\frac{1}{(1-0.50)}+\frac{2\times 0.50}{(1-0.50)^{2}}\\\\=2+4\\\\=6[/tex]
- Consider that Fred is at 2.
It is provided that Fred always moves to 1 if he at step 2.
e₂ : 2 4 6 8 ...
P (e₂) : 0.50 0.50² 0.50³ 0.50⁴ ...
The expected number of steps Fred takes to get to 0 if he is at 2 is:
[tex]e_{2}=(2\times 0.50)+(4\times 0.50^{2})+(6\times 0.50^{3})+(8\times 0.50^{4})+...\\\\[/tex]
The sum series e₂ is an AGP.
The sum of infinite AGP is:[tex]\frac{a}{1-r}+\frac{dr}{(1-r)^{2}}[/tex]
Then the value of e₂ is:
[tex]e_{1}=\frac{2}{(1-0.50)}+\frac{2\times 0.50}{(1-0.50)^{2}}\\\\=4+4\\\\=8[/tex]
Thus, the ordered pair (e₁, e₂) is (6, 8).
Answer:
(3, 4)
Step-by-step explanation:
For e_1, there is first a 1/2 chance that Fred will go to point 0 on the first move, giving us an expected value of 1/2. Similarily, there is 1/4 chance that Fred will go to point 0 on the 3rd move, giving us an expected value of 3/4th moves. We continue, and we see that the expected value for the number of moves is this.
[tex]1/2 + 3/4 + 5/8 + 7/16 + 9/32 + 11/64 ...[/tex]
This equation eventually equals to 3, so e_1 is equal to 3.
For e_2, it's just e_1 + 1, because Fred has to move to point 1 in the first place.
