You are here: Home End of chapter activity

Exercise 1: End of chapter activity

On a the probability scale below choose the which words best describe the probability of each of the following events:

1. The chance of visiting Mars.

2. The sun rising tomorrow morning.

3. Getting snow in the Kruger National Park in December.

4. The chance of getting rain in the Sahara Desert.

5. The chance of throwing Heads on a coin.

Fill in the numbers in this table to show probabilities in different number formats.

 Fraction (simplest form) Decimal fraction Percentage $$\frac{\text{3}}{\text{4}}$$ 0,75 0,3 10% 90% $$\frac{\text{1}}{\text{8}}$$
 Fraction (simplest form) Decimal fraction Percentage $$\frac{\text{3}}{\text{4}}$$ 0,75 75% $$\frac{\text{3}}{\text{10}}$$ 0,3 30% $$\frac{\text{1}}{\text{10}}$$ 0,1 10% $$\frac{\text{9}}{\text{10}}$$ 0,9 90% $$\frac{\text{1}}{\text{8}}$$ 0,125 12,5%

Look at the five-sided spinner shown in the diagram. When we spin the arrow, it has an equal chance of landing in each triangle, because they are all the same size.

1. List all the possible outcomes for getting an even number.

2. List all the possible outcomes for getting an odd number.

3. Is there an equal chance of getting an odd number and an even number? Explain.

4. How could you use this spinner to design an unfair game of chance?

1. 2; 4

2. 1; 3; 5

3. No, there is a higher chance of getting an odd number, because there are more possible outcomes for odd numbers.

4. The game would be unfair if a player has a small chance of winning, for example, if they win only if they get five. It would also be unfair if they win only if they get an even number.

1. Draw a tree diagram with the first set of branches showing the possible outcomes for spinning the spinner in question 3. Then add the outcomes for a coin toss to each of the branches.

2. How many possible outcomes are there altogether?

3. How many outcomes are there for getting a 4; H?

4. What is the probability of getting a 4; H?

5. How many outcomes are there for getting an even number and Heads? List them.

6. What is the probability of getting an even number and Heads?

1. Ten

2. Only one.

3. One in ten or $$\frac{\text{1}}{\text{10}}$$

4. Two: 2; H and 4; H

5. The probability is 2 in 10, which simplifies to 1 in 5 or $$\frac{\text{1}}{\text{5}}$$