EDEXCEL GCSE MATHS · FOUNDATION & HIGHER
Exam Practice: Combined Events
Combined events · Probability · Lesson 1 of 6 · 15 marks · 25 minutes
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Instructions
• Answer all the questions.
• Write your answers in the spaces provided.
• The marks for each question are shown in brackets - use this as a guide to how much to write.
• The answers are on separate pages at the back. Attempt every question before you look at them.
• Answer all questions. Show your working.
Question 1 NON-CALCULATOR (2 marks)
A fair coin is flipped and a fair dice is rolled. Write down the probability of getting a head and a 6.
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(Total for Question 1 = 2 marks)
Question 2 NON-CALCULATOR (3 marks)
Two fair dice are rolled and the scores are added. Work out the probability that the total is 7.
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(Total for Question 2 = 3 marks)
Question 3 NON-CALCULATOR (3 marks)
Spinner A has three equal sections numbered 1, 2 and 3. Spinner B has four equal sections numbered 1, 2, 3 and 4. Both spinners are spun and the two scores are added. Work out the probability that the total is 5.
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(Total for Question 3 = 3 marks)
Question 4 NON-CALCULATOR (2 marks)
For the same two spinners, work out the probability that the total is even.
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(Total for Question 4 = 2 marks)
Question 5 NON-CALCULATOR (3 marks)
Two fair dice are rolled and the scores are added. Work out the probability that the total is at least 10.
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(Total for Question 5 = 3 marks)
Question 6 NON-CALCULATOR (2 marks)
Two fair dice are rolled. Work out the probability of getting a double (the same number on both dice).
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(Total for Question 6 = 2 marks)
TOTAL FOR PAPER = 15 MARKS
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Answers and mark scheme
Check your answer only once you have written one.
Question 1 (2 marks)
There are 12 equally likely outcomes and one of them is H6. The probability is 1/12.
• 12 outcomes M1
• 1/12 A1
Question 2 (3 marks)
There are 36 equally likely outcomes and 6 give a total of 7. The probability is 6/36 = 1/6.
• 36 outcomes M1
• 6 successful outcomes M1
• 1/6 A1
Question 3 (3 marks)
There are 3 × 4 = 12 outcomes. The totals of 5 are (1, 4), (2, 3) and (3, 2), so the probability is 3/12 = ¼.
• 12 outcomes M1
• Three ways to make 5 M1
• ¼ A1
Question 4 (2 marks)
The even totals come from (1,1), (1,3), (3,1), (3,3), (2,2) and (2,4): 6 of 12. The probability is ½.
• 6 successful outcomes M1
• ½ A1
Question 5 (3 marks)
Totals of 10, 11 and 12 occur 3 + 2 + 1 = 6 times out of 36. The probability is 6/36 = 1/6.
• 6 successful outcomes M1
• 6/36 M1
• 1/6 A1
Question 6 (2 marks)
There are 6 doubles out of 36 outcomes, so the probability is 6/36 = 1/6.
• 6 doubles M1
• 1/6 A1