Answer ≈ 4 and a half billion
If we assume your letters range from A to Z and your digits from 0 to 9, you have 26 possibilities per letter and 10 per digit. This gives you 26^4*10^4 which is roughly 4 billion and a half.
Answer:
You have three card : 3, 4, and 5.
You first pick one card randomly, the probability of picking a 3 is:
P = 1/3
You then pick a second card without putting the first card back, the probability of picking a 5 is:
P = 1/2
=> The probability of picking a 3 and then picking a 5:
P = (1/3) x (1/2) = 1/6
Hope this helps!
:)
Answer: Just use MathPapa.
Step-by-step explanation:
Answer:
2.4 hours or 2 hours and 24 minutes
Step-by-step explanation:
Jack mows 1/6 of the lawn per hour while Marilyn mows 1/4 of the lawn together. Adding up those rates yields in their combined mowing rate:

The time required for them to mow the entire lawn is:

It would take them both 2.4 hours to mow the lawn together.
Answer:
a) 

b) 

c) For this case when we increase the sample size the margin of error would be lower and then the interval would be narrower
d)
(a)
Solving for n we got:
(b)
And replacing the info we have:

Step-by-step explanation:
Part a
For this case we have the following data given
represent the sample mean for the customer order totals
represent the population deviation
represent the sample size selected
The confidence level is 90% or 0.90 and the significance level would be
and
and the critical value from the normal standard distirbution would be given by:

And the confidence interval is given by:

And replacing we got:


Part b
The sample size is now n = 75, but the same confidence so the new interval would be:


Part c
For this case when we increase the sample size the margin of error would be lower and then the interval would be narrower
Part d
The margin of error is given by:
(a)
Solving for n we got:
(b)
And replacing the info we have:
