Answer:


And the 68% confidence interval is given by (91.1186, 97.2814)
Step-by-step explanation:
For this case we know that mean time that visitors stay at a museum is given by:

The standard deviation is given by:
And the standard error is given by:
And we want to interval captures 68% of the means for random samples of 25 scores and for this case the critical value can be founded like this using the normal standard distribution or excel:

We can find the interval like this:

And replacing we got:


And the 68% confidence interval is given by (91.1186, 97.2814)
Answer: 
Explanation:
Follow PEMDAS in reverse to undo what's happening to x.
We first add 1 to both sides, then divide both sides by 5 to fully isolate x.
Refer to the steps below to see what I mean.

The inequality sign stays the same the entire time. The only time it flips is when you divide both sides by a negative number.
The solution set for x is anything -3 or larger.
If x was an integer, then we could say the solution set is {-3, -2, -1, 0, 1, 2, 3, 4, 5, 6, ...}
Answer:
Step-by-step explanation:
Assuming the question is x^2 + 6x = 27x, subtract 6x from both sides. x^2 = 21x. Then, divide both sides by x and you get x= 0, 21
Answer:
the 4th one
Step-by-step explanation: