Answer:
$5 difference in rate at each step or change in hours.
Step-by-step explanation:
Answer:
Expected time is 15 hours for him to get to safety.
Step-by-step explanation:
We define X as the time that this miner would get to safety.
We define Y as the door he chooses initially.
P(Y= 1) = P(Y=2)=P(Y=3) = 1/3
We have E[X|Y=1] = 3
E[X|Y] = 5 hours + E[X}
E[X|Y] = 7 hours + E[X]
Then we have
E[X] = 1/3(3 + 5 + E[X] + 7 + E[X])
We cross multiply
3*E[X] = (15 + 2E[x])
3E[X] - 2E[X] = 15
E[X] = 15
So the time it would take to get him to safety is 15 hours
5.5 miles per hour ig bye
Answer:
20 units
Step-by-step explanation:
Initial particle concentration = 80 units
Particles removed each hour = 50% of the remaining particles
To find:
Particle concentration after 2 hours = ?
Solution:
Particles removed in 1 hour = 50% of remaining particles
i.e. Particles removed in 1 hour = 50% of initial concentration
Particles removed in 1 hour = 50% of 80 = 40
Particles removed in next 1 hour = 50% of remaining particles
i.e. Particles removed in next 1 hour = 50% of concentration after 1 hour
Particles removed in next 1 hour = 50% of 40 = 20
Total particles concentration removed in 2 hours = 40 + 20 = 60 units
Therefore, particle concentration after 2 hours = Initial concentration - Total particle concentration removed in 2 hours
= 80 - 60 = <em>20 units</em>
