Answer:
The mean is 4.5 and the standard deviation is 1.44.
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 of the uniform probability distribution is:

The standard deviation of the uniform probability distribution is:

Uniformly distributed random variable ranging from 2 to 7.
This means that
.
So


The mean is 4.5 and the standard deviation is 1.44.
For the first investment. A = P(1 + rt); where p = 9,720, r = 0.0316 and t = 1/12
A = 9720(1 + 0.0316/12) = 9720(1.0026) = $9,746
For the second investment,
A = 8140(1 + 0.0323 x 2) = 8140(1.0646) = $8,666
Total amount she had = $9,746 + $8,666 = $18,412
Answer:
20.33%
Step-by-step explanation:
We have that the mean (m) is equal to 87.5, the standard deviation (sd) 6.25 and the sample size (n) = 12
They ask us for P (x <86)
For this, the first thing is to calculate z, which is given by the following equation:
z = (x - m) / (sd / (n ^ 1/2))
We have all these values, replacing we have:
z = (86 - 87.5) / (6.25 / (12 ^ 1/2))
z = -0.83
With the normal distribution table (attached), we have that at that value, the probability is:
P (z <-0.83) = 0.2033
The probability is 20.33%
It took her 45 minutes to rest and it to her 45 minutes to bike the initial 8 miles. or .75 hours for both