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# Statistics Help - Arrangement/Permutation/Combinations watch

1. Hi,
I was hoping that you could help me a couple of questions.

1) I have 7 yoghurts to last me a week: 2 Strawberry; 2 Peach; 3 Raspberry. I select one yoghurt each day.
a) In how many different orders can I eat the yogurts?
b) If i select a yogurt at random each day, what is the probability that I eat the two srawberry ones on consecutive days?

-Is part a just 7P7, so 5040?

2) A class contains 30 children, 18 are femal and 12 are boys. Four theartre tickets are being randomly distrbuted. What is the probability that:
a) all four tickets go to girls
b) two boys and two girls recieve the tickets

- would part a be 18C4 / 30C4?
-would part b be (18C2 x12C2) / 30C4?
2. a) (18/30)*(17/29)*(16/28)*(15/27)
b) (18/30)*(17/29)*(12/28)*(11/27)/(4C2)
3. (Original post by Alexia_17)
-Is part a just 7P7, so 5040?
No, you have overcounted. You will need to divide 7P7 by some factors based on the fact there are multiple ice creams of each flavour.
4. (Original post by etothepiiplusone)
No, you have overcounted. You will need to divide 7P7 by some factors based on the fact there are multiple ice creams of each flavour.
Thank you, would you mind helping me out on question 2?
5. (Original post by Alexia_17)
Thank you, would you mind helping me out on question 2 on my other post.... https://www.thestudentroom.co.uk/sho....php?t=4990330
So you now know the answer?
6. (Original post by etothepiiplusone)
So you now know the answer?
I know the answer to Question 1 now.

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