X is the number of weeks he is exercising starting summer
f(x) is number of total hours he exercised
2(18+11)
i think this is the expression you are looking for
Answer:
1,496 new car buyers
Step-by-step explanation:
The sample size n in Simple Random Sampling is given by

where
z = 1.645 is the critical value for a 90% confidence level (*)
p= 0.33 is the population proportion.
e = 0.02 is the margin of error
so

<em>(*)</em><em>This is a point z such that the area under the Normal curve N(0,1) inside the interval [-z, z] equals 90% = 0.9</em>
It can be obtained in Excel or OpenOffice Calc with
<em>NORMSINV(0.95)</em>
Approximately 70% of the visitors to the theme park are older than about 12.3.
A z-score of about -0.53 is position on the normal distribution for finding the amount above 30% (70%).
Therefore, we can write and solve the following equation:
(x - 15) / 5.2 = -0.53
x - 15 = -2.756
x = 12.244
The closest amount is 12.3.
I believe the answer is 3/8. The whole portion of employees, which is translated as 8/8 is deducted by 5/8, which is the population of male employees.