Statistics and Probability

Suppose you toss a coin several times and record the results. Out of 20 trials, you got tails 11 times. How does this compare to the theoretical probability?

• more often

• less often

• exactly the same

The results for a survey of 120 students who were selected randomly are listed below: 60 students have a cell phone plan with company X, 36 students have a plan with company Y, 24 students do not have a cell phone. The total population of students was 380. Based on the data, what is the best approximation for the total number of students who have a cell phone plan with company Y?

• 114

• 127

• 143

• 163

This board game spinner is divided into sections of equal size. What is a reasonable estimate of the number of times the spinner will land on a section labeled 5 over the course of 150 spins?

• 2

• 20

• 30

• 50

Hilda has a fair number pyramid with four faces (numbered 1-4) and a spinner with three equal-sized colored sections (red, blue, green). What is the probability that the number pyramid will land on three AND the spinner will stop on blue?

• 1/12

• 3/12

• 4/12

• 7/12

A coin is tossed and a fair die is rolled. Find P(heads, greater than 3).

• 1/6

• 1/4

• 5/6

• 4/5

You roll a fair number cube. What is the probability of getting a 2 or a 5?

• 1/6

• 2/6

• 3/6

• 4/6

What is the IQR of this data set?

• 470

• 320

• 160

• 100

How many times can you expect to roll a 2 or 3 in 120 consecutive rolls of a fair die?

• 30

• 40

• 50

• 60

The owner of a small store knows that in the last week 54 customers paid with cash, 42 paid with a debit card, and 153 paid with a credit card. Based on the number of customers from last week, which fraction is closest to the probability that the next customer will pay with cash?

• 1/5

• 1/4

• 1/3

• 1/2

Suppose you have a bag that contains 4 black, 3 green, 1 red, and 2 orange marbles. Find P (not orange). Express your answer as an exact decimal.