Answer:
The mean is 11.5 minutes and the standard deviation is of 6.64 minutes
Step-by-step explanation:
An uniform probability is a case of probability in which each outcome is equally as likely.
For this situation, we have a lower limit of the distribution that we call a and an upper limit that we call b.
The mean is:

The standard deviation is:

Arrival time of 9:18 am and a late arrival time of 9:41 am.
9:41 is 23 minutes from 9:18. So the time is uniformily distributed between 0 and 23 minutes, so a = 0, b = 23.
Mean:

Standard deviation:

The mean is 11.5 minutes and the standard deviation is of 6.64 minutes
X + 3x + 4x = 56
8x = 56
x = 7
The shortest piece is 7 inches
The middle piece is 7*3 = 21 inches.
The longest piece is 4*7 = 28 inches
Check
7 + 21 + 28 = 56 It does check and the lengths are correct.
Answer: 3/55
Step-by-step explanation:
From the information given, the bag contains 3 red, 3 orange, 1 yellow, 2 purple marbles, and 2 Pink marbles. Each time he picks an orange marble, she will win a prize.
If he picks a marble the first time, the probability of picking an orange marble will be 3/11. After that we will have 10 marbles left as one has been picked and have 2 orange marbles left, then the probability of picking another orange marble will be 2/10.
Therefore, the probability he will win a prize on both picks will be:
= 3/11 × 2/10
= 6/110
= 3/55