Answer:
628
Step-by-step explanation:
We have the standard deviation of the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 12 - 1 = 11
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 11 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.2
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 665 - 37 = 628 hours.
The answer is 628
In this question, we're trying to find the cost of feeding the cats for a year.
We know that we use 12 cans to feed the cats
We also know that each can costs $0.60
To find how much the cafeteria spent on the cats, we need to see how much 12 cans cost, and multiply that by 52 to get our yearly cost
Solve:
12 · 0.60 = 7.2
12 cans = $7.20
Now multiply 7.20 by 52 to get our minimum yearly cost for the cats.
52 · 7.20 = 374.4
This means that it costs $374.4 to feed the cats for a year.
Answer
$374.40
Let the numerator = x. Then,
The fraction is x/(3x+4).
If both the numerator and denominator are increased by 4, the fraction will be (x+4)/(3x+8), which, according to the question is equal to 9/25. So,
(x+4)/(3x+8) = 9/25
25(x+4) = 9(3x+8)
25x + 100 = 27x + 72
2x = 28
x = 14
Thus, the numerator is 14 and the denominator is (3*14 + 4), which is equal to 46. So the fraction is 14/46.
It’s 6 none of those r correct
