Maths Quest a Year 11 for Queensland Chapter 12 Introduction to Probability Worksheet 12.2 1

Maths Quest A Year 11 for Queensland Chapter 12 Introduction to probability WorkSHEET 12.2 1

WorkSHEET 12.2 Introduction to probability Name: ______

1 A fair coin is tossed 50 times and a head came up 15 times.

(a) Find the relative frequency of obtaining a head, as a fraction.

(b) Calculate the relative frequency of obtaining a tail, as a decimal.

2 5 The probability of my winning a raffle is . 60 If I bought twelve tickets in the raffle, what is the total number of tickets that must have been sold?

3 A bingo card is numbered from 11 to 20. What is the probability that the winning number will be:

(a) 11?

(b) an even number?

(c) a prime number?

4 Jason enters the library and chooses a book randomly from a shelf containing 5 fiction, 7 non-fiction and 9 science-fiction books. What is the probability of him:

(a) choosing a non-fiction book

(b) not choosing a fiction book

(c) choosing a science-fiction or fiction book.

5 Order the following probabilities from least likely to occur to most likely to occur.

3 6 45%, 0.5, 12%, , 0.8, 100% , 0, 4 10 Maths Quest A Year 11 for Queensland Chapter 12 Introduction to probability WorkSHEET 12.2 2

6 Two coins are tossed. Find the probability of obtaining:

(a) 2 heads

(b) a head then a tail

(c) one of each.

7 Ben has a choice of cereal or toast and of milk or juice. What is the probability of him having:

(a) cereal and juice?

(b) toast and milk?

(c) juice?

8 A bag contains one black and two red marbles. Joe picks a marble and its colour is noted then it is replaced. A second marble is then picked. What is the probability of getting:

(a) two red marbles?

(b) different coloured marbles?

(c) a black then a red marble?

9 A die is rolled and a coin is tossed. What is the probability of:

(a) getting a head?

(b) an even number?

(c) a tail and a 3?

(d) a head and an odd number? Maths Quest A Year 11 for Queensland Chapter 12 Introduction to probability WorkSHEET 12.2 3

10 A bag contains green, red and black coloured disks. From the number of each colour of disk in the bag, the following probabilities were determined for an experiment involving the removal of one disk from the bag.

1 P (green) = 8 3 P (red) = 8

Determine the probability of drawing a black-coloured disk from the bag.