1. Choose level of difficulty
Probability
Ronan is designing a game.
He has two sets of discs laid face down on a table.
The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Ronan uses the game to raise money for charity.
Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Choose level of difficulty

2. Probability The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Help
Step 1: Fill in sample space
diagram.
Two discs are added together so we must draw a sample space diagram.

3. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Help
Step 2: Work out the
probability of
getting exactly 13.
How many possible numbers are there?
How many 13’s are there? 5 7 9 11 5 7 9 11 13 7 9 11 13 15 9 11 13 15 17

4. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Help
Step 3: Work out how much money he takes.
100 people play the game each paying 20p.

5. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Probability of winning =
Help
Step 4: Work out how many people you expect to win.
Probability of winning multiplied by number of players.

6. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
Number of winners = 15
Help
Step 5: Work out cost of prizes.
Number of winners multiplied by cost of prize.

7. Probability
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Cost of prizes = £7.50
Money taken = £20
Help
Step 6: Work out money raised.
Cost of prizes subtracted from money taken.
End of Problem
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8. Probability The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Help
Step 1: Fill in sample space
diagram.
Two discs are added together so we must draw a sample space diagram.

9. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Help
Step 2: Work out the
probability of
getting exactly 13.
How many possible numbers are there?
How many 13’s are there? 5 7 9 11 5 7 9 11 13 7 9 11 13 15 9 11 13 15 17

10. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Help
Step 3: Work out how much money he takes.
100 people play the game each paying 20p.

11. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Probability of winning =
Help
Step 4: Work out how many people you expect to win.
Probability of winning multiplied by number of players.

12. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
Number of winners = 15
Help
Step 5: Work out cost of prizes.
Number of winners multiplied by cost of prize.

13. Probability
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Cost of prizes = £7.50
Money taken = £20
Help
Step 6: Work out money raised.
Cost of prizes subtracted from money taken.
End of Problem
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14. Probability The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.

15. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity. 5 7 9 11 5 7 9 11 13 7 9 11 13 15 9 11 13 15 17

16. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.

17. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Probability of winning =

18. Probability Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
Number of winners = 15

19. Probability
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Cost of prizes = £7.50
Money taken = £20
End of Problem
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20. Probability Ronan is designing a game.
He has two sets of discs laid face down on a table.
The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Hint
Fill in the grid

21. Probability Ronan is designing a game.
He has two sets of discs laid face down on a table.
The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Ronan uses the game to raise money for charity.
Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Hint
Probability and takings?

22. Probability Ronan is designing a game.
He has two sets of discs laid face down on a table.
The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Ronan uses the game to raise money for charity.
Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Hint
Costs?
End of Problem
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23. Probability Ronan is designing a game.
He has two sets of discs laid face down on a table.
The first set of five discs are labelled 1, 3, 5, 7, 9
The second set of four discs are labelled 2, 4, 6, 8
Players turn over one disc, at random, from each set and add the numbers together.
Ronan uses the game to raise money for charity.
Each player pays 20p to play the game.
If a player gets a total of exactly 13 they win a bar of chocolate.
It costs Ronan 50p for each bar of chocolate.
If 100 people play the game, show that Ronan should expect to raise £12.50 for charity.
Hint
Use the grid below
End of Problem
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