Proportions or Means AP Stat

Your mail-order company advertises that it ships 90% of its orders within three working days. You select an SRS of 100 of the 5000 orders received in the past week for an audit.

What is the standard deviation?

• 0.04

• 0.004

• 0.3

• 0.03

Your mail-order company advertises that it ships 90% of its orders within three working days. You select an SRS of 100 of the 5000 orders received in the past week for an audit.<\/p>

What Is the probability that more than 95% of the orders are delivered within three working days? <\/p>

• 0.0228<\/p>

• 0.4779<\/p>

• 0.0478<\/p>

• 0.9522<\/p>

According to government data, 22% of American children under the age of six live in households with incomes less than the official poverty level. A study of learning in early childhood chooses an SRS of 400 children. What is the probability that between 15% and 25% of children live in households with less than the official poverty level?

• 0.9998

• 0.0007

• 0.9259

• 1

• 0

According to government data, 22% of American children under the age of six live in households with incomes less than the official poverty level. A study of learning in early childhood chooses an SRS of 400 children. What is the probability that at most 16% of children live in households with less than the official poverty level?

• 0.0003

• 0.0019

• 0.9968

• 0.9999

• 0

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%

Identify the population

• 20 game pieces

• p = 25%

• p-hat = 15%

• All game pieces

Identify the sample

• 20 game pieces

• 25%

• 3 instant winners

• All game pieces

Identify the parameter

• 20 game pieces

• p = 25%

• 3 instant winners

• p-hat = 3/20 = 15%

Identify the statistic

• 20 game pieces

• p = 25%

• 3 instant winners

• p-hat = 3/20 = 15%

What does the dot above .05 represent?

• 5% of the sample proportions had 1 instant winner out of 20.

• In a single sample of 20 game pieces, 1/20 (5%) were instant winners.

• There is a .05 chance of getting 1 instant winner in a sample of 20 pieces.