Population Proportions

Suppose we have a population that is 49% male.  If we take a random sample from that population and determine the percent of our sample that is male, we refer to this proportion as...

• p

• p-hat
  

• the sample mean

• the sampling distribution

When sampling from a population with proportion p, the distribution of sample proportions (p-hat) will vary. What will be the mean of all possible sample proportions?

• p

A sample is taken of 200 people. The number of people who own a dog was 80.
What is the sample proportion?

• 80

• 0.8

• 0.4

• 35%

30% of all dogs in a city are micro-chipped. In a sample of 500 dogs, what is the probability that less than 140 dogs are micro-chipped? Select the closest option.

• 0.25

• 0.21

• 0.17

• 0.13

What does this formula do?

• Calculates Standard Deviation

• Checks if the samples are independent

• Checks Normality

• Calculates Probabilities

It was found that in a sample of 90 teenage boys, 63 of them have received speeding tickets.  What is the 90% confidence interval of the true proportion of teenage boys who have received speeding tickets? 

• (0.621, 0.780)

• (0.591, 0.812)

• (0.584, 0.830)

• (0.615, 0.805)

A survey of 800 women shoppers found that 136 of them shop on impulse.  What is the 98% confidence interval for the true proportion of women shoppers who shop on impulse? 

• 0.148 < p < 0.192

• 0.136 < p < 0.204

• 0.144 < p < 0.196

• 0.139 < p < 0.201

What does this symbol represent?

• parameter

• sample proportion

• parameter of a population

• population proportion