Answer:
48.
Step-by-step explanation:
33 + 15 = 48.
You can check your answer by subtracting 48-15, which gives you 33.
Answer:
X is 9
Step-by-step explanation:
9 + 3 = 12
Answer:
a) P=0.535
b) P=0.204
c) P=0.286
Step-by-step explanation:
The exponential distribution is expressed as

In this example, λ=1/8=0.125 min⁻¹.
a) The probability of having to wait more than 5 minutes

b) The probability of having to wait between 10 and 20 minutes

c) The exponential distribution is memory-less, so it is independent of past events.
If you have waited 5 minutes, the probability of waiting more than 15 minutes in total is the same as the probability of waiting 15-5=10 minutes.

5x +y = 6
5x + 3y = -4
multiply top equation by -1 and bottom by 1
-5x -y = -6
5x+3y = -4
solve and get
2y = -10
y = -10/2
y = -5
answer is -5