Answer:
Freshman: 3.245
Sophomore: 3.0775
All: 3.16125
Step-by-step explanation:
Freshman: (B+) + (B+) + (A-) + (B-) /(4lessons)
(3.33 + 3.33 + 3.66 + 2.66)/4=12.98/4=3.245
Sophomore: (B-) + (C+) + (A-) +(A-) /4
(2.66 + 2.33 + 3.66 + 3.66)/4 = 12.31/4= 3.0775
All: (3.245 + 3.0775)/2=6.3225/2=3.16125
the domain is all the real numbers, or (-infinite <x<infinite)
the range is y>=-4
axis of symetry is x= -1
vertex is (-1,-4)
the parabola opens upwards
x intercepts (-3,0) and (1,0)
y intercepts (0,-3)
3 + 1 < 10
There's no question there, and nothing to solve. That's a simple statement
which, after simplifying it slightly, says " 4 < 10 ".
A statement with which, I'm sure, we can all agree.
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
