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# Probability help watch

1. Hi I've tried this question and I'm a bit stuck.

Poppy rolls a dice. She keeps rolling until she rolls a 6. Work out the probability that Poppy rolls the dice:

a)exactly three times
b)fewer than three times
c) more than three times
2. What is the probability that she doesnt roll a six in one throw?

What is the probability that she rolls a six in one throw?
3. What is the probability of rolling a non-6? A 6?

a. Three times requires non-6, non-6, 6
b. Requires 6 OR non-6, 6
c. Requires non-6, non-6, non-6
4. (Original post by Shaanv)
What is the probability that she doesnt roll a six in one throw?

What is the probability that she rolls a six in one throw?
P(not6)=5/6
P(6)=1/6
5. (Original post by isabel12144)
P(not6)=5/6
P(6)=1/6
OK.

a). So, to end up rolling the die exactly 3 times:

What must she roll on the third throw?
And what must she roll on each of the other two throws?

Hence probability of exactly 3 rolls is...?

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