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
2(3-4a) + 5(a-7) first do the distributive property
6-8a + 5a-35 now combine like terms
-41 - 3a is the final answer
9514 1404 393
Answer:
Step-by-step explanation:
Let d represent the number of daffodil bulbs you buy. Then 60-d is the number of crocus bulbs. The total cost will be ...
0.45(60 -d) +0.65(d) = 35.00
27 +0.20d = 35
0.20d = 8 . . . . . . . . . subtract 27
d = 40 . . . . . . . . . . multiply by 5
60 -40 = 20 . . . . . crocus bulbs
You can buy 20 crocus bulbs and 40 daffodil bulbs for $35.
Answer:
The y-intercept would be 4
Step-by-step explanation: