Sasha Shasha
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The probability that Sue completes a Sudoku puzzle correctly is 0.75.
(i) Sue attempts n Sudoku puzzles. Find the least value of n for which the probability that she
completes all n puzzles correctly is less than 0.06. [3]
Sue attempts 14 Sudoku puzzles every month. The number that she completes successfully is denoted
by X.
(ii) Find the value of X that has the highest probability. You may assume that this value is one of the
two values closest to the mean of X. [3]
(iii) Find the probability that in exactly 3 of the next 5 months Sue completes more than 11 Sudoku
puzzles correctly. [5]
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RDKGames
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You have my blessings with this question, go for it.
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Sasha Shasha
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#3
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Thank You
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ghostwalker
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(Original post by Sasha Shasha)
...
If you're still stuck, post any relevant working so far, and say where you're stuck - and do have a read of the forum guidelines; sticky post at the top of the forum.
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Sasha Shasha
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(Original post by ghostwalker)
If you're still stuck, post any relevant working so far, and say where you're stuck - and do have a read of the forum guidelines; sticky post at the top of the forum.
The first question itself , in marking scheme they've used log to solve it but i wonder why they use that
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Idg a damn
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well you need to solve this inequality:

0.75^n<0.06

so you need the log function to solve it
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ghostwalker
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(Original post by Sasha Shasha)
The first question itself , in marking scheme they've used log to solve it but i wonder why they use that
Well you could work out the probability of 1 out of 1 correct, 2 out of 2 correct, and so on, until you find a value less than 0.06. But that would be rather tedious if n was any decent size.

Instead, you can go their directly, via the inequality ldg a damn gave, and for that you would need to use logs.
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Sasha Shasha
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(Original post by ghostwalker)
Well you could work out the probability of 1 out of 1 correct, 2 out of 2 correct, and so on, until you find a value less than 0.06. But that would be rather tedious if n was any decent size.

Instead, you can go their directly, via the inequality ldg a damn gave, and for that you would need to use logs.
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Sasha Shasha
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(Original post by Idg a damn)
well you need to solve this inequality:

0.75^n<0.06

so you need the log function to solve it
Thank You
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