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# How am I wrong? Watch

1. https://869d950bf149eefd5cd2652b4001...%20Edexcel.pdf

Question 7 d

I arranged the problem as
2*p(x-u < 1) >= 0.98

p(x-u<1) >= 0.49

But when I solve this I end up with n = 4.26, rather than 48.7.
2. (Original post by Armpits)
https://869d950bf149eefd5cd2652b4001...%20Edexcel.pdf

Question 7 d

I arranged the problem as
2*p(x-u < 1) >= 0.98
Should be 2P(x-u < 1) - 1 >= 0.98.
3. (Original post by Zacken)
Should be 2P(x-u < 1) - 1 >= 0.98.
Ah yes of course. Thanks a lot!
4. (Original post by Armpits)
Ah yes of course. Thanks a lot!
No worries.

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