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Medium

Zombie Probability TreesIt’s the zombie apocalypse! There are zombies everywhere. Work out the probability of your survival using the data below. You can use the RED NUMBERS for extra challenge:

Day 1:

P (N /Bitten )=340.91

P (Bitte n )=149%

Day 2:

P (N /Bitten )=230.53

P (Bitten )=1347%

Day 3:

P (N /Bitten )=14911

P (Bitten )=34211

1. Draw a probability tree to show all outcomes. 2. What is the probability that you urvive the first two days without being

bitten?3. What is the probability that you get bitten every single day (ouch!)4. What is the probability that you only get bitten on the third day?5. What is the probability that you never get bitten?

You will need to use OR (+) for these questions:6. What is the probability that you get bitten twice?7. What is the probability that you don’t get bitten on the third day?8. What is the probability that you only get bitten on the second day?

You need to go out on a supply run! Calculate the probability of your survival using the data below. You can use the RED NUMBERS for extra challenge:

Day 1:

P (No Attack )=58710

P (Min. Attack )=1820%

P (Maj. Attack )=140.1

Day 2:

P (No Attack )=270.02

P (Min. Attack )=4725%

P (Maj. Attack )=1773100

Day 3:

P (No Attack )=1416%

P (Min. Attack )=120.8

P (Maj. Attack )=14125

9. Draw a probability tree to show all outcomes10. What is the probability that you encounter no attacks at all?11. What is the probability that you encounter minor attacks every day?12. What is the probability that you encounter major attacks on the first two

days, and no attack on day 3?

You need to use OR (+) for these questions:13. What is the probability of only being attacked on the third day?14. What is the probability of suffering two major attacks?

15. What is the probability of suffering attacks on all days?

Zombie Probability Trees (Conditional)You are a hungry zombie! You have found a camp of survivors outside of town. You randomly munch on the brains of one person a day for three days. The people in the camp are shown below.

Copy and complete the probability tree below.

Remember there’ll be one less person each day!

1. What is the probability that 3 male survivors get eaten?2. What is the probability that 3 female survivors get eaten?3. What is the probability that you eat in this order: M,F,M?4. What is the probability that you eat in this order: F,F,M?5. What is the probability that you eat in this order: M,M,F?

You will need to use OR (+) to answer these questions6. What is the probability that only 1 male survivor gets eaten?7. What is the probability that only 1 female survivor gets eaten?8. What is the probability that a male survivor gets eaten on the second day?

Day 1 Day 2 Day 3

P(Male)

P(Female)

9. What is the probability that a female survivor gets eaten on the last day?10. What is the probability that a male survivor gets eaten on the first and last

days?