Answer:
23.44%
Step-by-step explanation:
The probability of getting a 4 on the first 2 throws and different numbers on the last 5 throws = 1/6 * 1/6 * (5/6)^5
= 0.01116
There are 7C2 ways of the 2 4's being in different positions
= 7*6 / 2 = 21 ways.
So the required probability = 0.01116 * 21
= 0.2344 or 23.44%.
Answer:12
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
Answer:
6/-12 = -1/2
Step-by-step explanation:
do you want an explanation?
btw, plz brainliest :)
Answer:
Step-by-step explanation:
We want to determine a 90% confidence interval for the mean amount of time that teens spend online each week.
Number of sample, n = 41
Mean, u = 43.1 hours
Standard deviation, s = 5.91 hours
For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean +/- z ×standard deviation/√n
It becomes
43.1 ± 1.645 × 5.91/√41
= 43.1 ± 1.645 × 0.923
= 43.1 ± 1.52
The lower end of the confidence interval is 43.1 - 1.52 =41.58
The upper end of the confidence interval is 43.1 + 1.52 =44.62
Therefore, with 90% confidence interval, the mean amount of time that teens spend online each week is between 41.58 and 44.62
