Act Math Probability

 Kyle has been tossing a coin and recording the number of heads and tails results. What is the probability that he will get tails 6 times in a row?

Tom is in Ms. Zhu’s class. To choose 4 students from her class of 24 students to answer questions, Ms. Zhu will put 24 cards, each with the name of a different student from her class on it, in a box. Next, Ms. Zhu will randomly draw 4 cards from the box without replacing any of the cards. What is the probability that Tom’s card will NOT be drawn?

A bag contains several marbles. On 3 successive draws with replacement, a red marble is drawn from the bag each time. Which of the following statements must be true about the marbles in the bag?

• At least 1 marble is red.

• Exactly 1 marble is red.

• Exactly 3 marbles are red.

• All the marbles are red.

• The bag contains more red marbles than marbles of other colors.

What is the probability of selecting the letter M or T, if from the letters M, A, T, H, E, M, A, T, I, C, S, a single letter is drawn randomly?

The probability of randomly selecting a green marble from a bag is 45. If there are 110 marbles in the bag, how many are NOT green?

• 11

• 22

• 30

• 88

• 110

Andre’s Floral Shop asked each of 20 customers to give a rating of the shop’s service. The table summarizes the 20 customer ratings. Which of the following values is closest to the mean of the 20 customer ratings?

• 1.8

• 2.0

• 2.3

• 2.7

• 3.3

• 0

• 2

• 9

For which of the following data sets is the difference between the mean and the median the greatest?

• {10, 10, 10, 10}

• {10, 10, 15, 20}

• {10, 15, 15, 15}

• {10, 15, 15, 100}

• {10, 20, 90, 100}

The mean of a list of 7 numbers is 85. The first 6 numbers on the list are 82, 93, 68, 93, 70, and 98. What is the 7th number on the list?

• 61

• 84

• 88

• 91

• 92

A retailer’s website allows shoppers to customize the shoes they order. Customers may select one of three different colors, one of two types of laces, and one of eight special logos. With these choices, how many different shoe designs are possible?

• 13

• 14

• 41

• 46

• 48