Math 9 · Unit 12: Probability · Cambridge Lower Secondary Maths Stage 9

Questions

1. 1. A bag has 12 balls numbered 1, 1, 1, 1, 2, 2, 2, 3, 5, 8, 8, 9. A ball is chosen at random. What is the probability that the number is 1?

   • 4/8
   • 1/3
   • 1/4
   • 1/12
   Check

2. 2. A bag has 12 balls numbered 1, 1, 1, 1, 2, 2, 2, 3, 5, 8, 8, 9. A ball is chosen at random. What is the probability that the number is NOT 1?

   • 1/3
   • 11/12
   • 2/3
   • 8/9
   Check

3. 3. A bag has 12 balls numbered 1, 1, 1, 1, 2, 2, 2, 3, 5, 8, 8, 9. A ball is chosen at random. What is the probability that the number is more than 6?

   • 1/4
   • 1/2
   • 3/9
   • 1/3
   Check

4. 4. A bag has 12 balls numbered 1, 1, 1, 1, 2, 2, 2, 3, 5, 8, 8, 9. A ball is chosen at random. What is the probability that the number is even?

   • 7/12
   • 1/2
   • 5/12
   • 3/12
   Check

5. 5. A bag has 12 balls numbered 1, 1, 1, 1, 2, 2, 2, 3, 5, 8, 8, 9. A ball is chosen at random. What is the probability that the number is odd?

   • 5/12
   • 4/12
   • 7/12
   • 1/2
   Check

6. 6. A runner is in a race. The probability that he will win is 0.1. The probability that he will come second is 0.25. The probability that he will come third is 0.45. Work out the probability that he will come first or second.

   • 0.55
   • 0.025
   • 0.8
   • 0.35
   Check

7. 7. A runner is in a race. The probability that he will win is 0.1. The probability that he will come second is 0.25. The probability that he will come third is 0.45. Work out the probability that he will not be in the first three.

   • 0.55
   • 0.2
   • 0.8
   • 0.45
   Check

8. 8. The temperature at midday tomorrow will be higher, lower or the same as the temperature at midday today. The probability that it will be higher is 15%. The probability that it will be lower is 65%. Work out the probability that the temperature will not be higher.

   • 65%
   • 85%
   • 15%
   • 35%
   Check

9. 9. The temperature at midday tomorrow will be higher, lower or the same as the temperature at midday today. The probability that it will be higher is 15%. The probability that it will be lower is 65%. Work out the probability that the temperature will not be lower.

   • 85%
   • 65%
   • 15%
   • 35%
   Check

10. 10. The temperature at midday tomorrow will be higher, lower or the same as the temperature at midday today. The probability that it will be higher is 15%. The probability that it will be lower is 65%. Work out the probability that the temperature will be the same.

    • 35%
    • 50%
    • 80%
    • 20%
    Check

11. 11. There are 50 cars in a car park. 15 cars are silver, 8 cars are white and 9 cars are black. A car is chosen at random. Work out the probability that the car is black or white.

    • 9/50
    • 72/2500
    • 17/50
    • 8/50
    Check

12. 12. There are 50 cars in a car park. 15 cars are silver, 8 cars are white and 9 cars are black. A car is chosen at random. Work out the probability that the car is not silver.

    • 7/10
    • 3/10
    • 35/15
    • 17/50
    Check

13. 13. There are 50 cars in a car park. 15 cars are silver, 8 cars are white and 9 cars are black. A car is chosen at random. Work out the probability that the car is neither silver nor black.

    • 1/2
    • 8/50
    • 24/50
    • 13/25
    Check

14. 14. There are 5 colours on a spinner. The table shows the probabilities of landing on different colours. Find the probability of landing on: i green or blue, ii not blue.

    • 0.55 and 0.75
    • 0.035 and 0.65
    • 0.45 and 0.35
    • 0.45 and 0.65
    Check

15. 15. There are 5 colours on a spinner. The table shows the probabilities of landing on different colours. Orange and red are equally likely. Find the probability of not landing on red.

    • 0.15
    • 0.85
    • 0.3
    • 0.7
    Check

16. 16. There are 12 coloured counters in a bag. The counters are black, white or grey. A counter is chosen at random. The probability that the counter is not black is 3/4. The probability that the counter is not white is 2/3. Work out the probability that the counter is grey.

    • 7/12
    • 1/3
    • 5/12
    • 1/4
    Check

17. 17. Ten letters are written on cards. A card is chosen at random. Work out the probability that the letter is in the word ADDITION.

    • 1/10
    • 1/2
    • 2/5
    • 3/10
    Check

18. 18. Ten letters are written on cards. A card is chosen at random. Work out the probability that the letter is in the word SUBTRACTION.

    • 8/10
    • 3/10
    • 9/10
    • 1/10
    Check

19. 19. There are 100 tickets, numbered from 1 to 100, in a box. One ticket is chosen at random. Find the probability that the ticket is the number 37.

    • 1/100
    • 37/100
    • 63/100
    • 1/37
    Check

20. 20. There are 100 tickets, numbered from 1 to 100, in a box. One ticket is chosen at random. Find the probability that the ticket is not 99 or 100.

    • 1/100
    • 99/100
    • 98/100
    • 2/100
    Check