Answer:
The population proportion is estimated to be with 99% confidence within the interval (0.1238, 0.2012).
Step-by-step explanation:
The formula for estimating the population proportion by a confidence interval is given by:
Where:
is the sample's proportion of success, which in this case is the people that regularly lie during surveys,
is the critical value needed to find the tails of distribution related to the confidence level,
is the sample's size.
<u>First</u> we compute the value:
<u>Next</u> we find the z-score at any z-distribution table or app (in this case i've used StatKey):
Now we can replace in the formula with the obtained values to compute the confidence interval:
Answer:
Option D (r(t) = 3.50t +25
; r(8) = 53)
Step-by-step explanation:
The fixed cost to rent the kayak $25. This is the cost which remains fixed irrespective of the usage of the kayak. The variable cost of using the kayak is the cost which depends on the usage of the kayak. It is mentioned that the kayak is used for 4 hours and the company charges $3.5 for every half hour. The cost function is given by:
r(t) = 25 + 3.5t ; there r is the total cost of using the kayak and t is the number of half-hours the kayak is used.
4 hours means that there are 8 half-hours. Therefore, t=8. Put t=8 in r(t).
r(8) = 25 + 3.5*(8) = 25 + 28 = 53.
Therefore, Option D is the correct answer!!!
