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Mathematics: Post your doubts here!

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I need help!

It is claimed that a certain 6-sided die is biased so that it is more likely to show a six than if it was fair.
In order to test this claim at the 10% significance level, the die is thrown 10 times and the number of sixes is noted.
(i) Given that the die shows a six on 3 of the 10 throws, carry out the test.

On another occasion the same test is carried out again.
(ii) Find the probability of a Type I error.


I got part (i) right (0.225), but I can't understand how I'm supposed to attempt part two. The answer to (ii) is 0.0697.
 
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I need help!

It is claimed that a certain 6-sided die is biased so that it is more likely to show a six than if it was fair.
In order to test this claim at the 10% significance level, the die is thrown 10 times and the number of sixes is noted.
(i) Given that the die shows a six on 3 of the 10 throws, carry out the test.

On another occasion the same test is carried out again.
(ii) Find the probability of a Type I error.


I got part (i) right (0.225), but I can't understand how I'm supposed to attempt part two. The answer to (ii) is 0.0697.
Part i is related to part ii here I guess.
So if you let the number of sixes thrown be X
You need to find out the P(X>=4)
Probabiilty of success is 1/6
probability of failure is 5/6
Just use the binomial formula and you'll get the answer.
 
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View attachment 58958
Parts ii and iii please
For part ii. Rearrange the equation:
sina - ((1.5-cosa)/a)
Put 1 and calculate. Then put 2 and calculate. You will notice a change in the signs of your answer. Second one will be positive and so just write a statement that since the answer is negative when a is 1 and positive when a is greater than 1 then a is by calculation greater than 1

For part iii. Use a1 as 1 and keep calculating like other iterations. Stop when you start getting the same answer on ur calculator. That will be your answer. :)
 
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upload_2016-1-26_13-12-15.png
Parts ii and iii please ... I'm stuck on ii so I can't go onto iii either and the ms is confusing me how to plot it....
upload_2016-1-26_13-13-24.png
Why do we need a bisector for part ii ...
Please can you solve and explain this question? :confused:
Anum96
 
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For part ii. Rearrange the equation:
sina - ((1.5-cosa)/a)
Put 1 and calculate. Then put 2 and calculate. You will notice a change in the signs of your answer. Second one will be positive and so just write a statement that since the answer is negative when a is 1 and positive when a is greater than 1 then a is by calculation greater than 1

For part iii. Use a1 as 1 and keep calculating like other iterations. Stop when you start getting the same answer on ur calculator. That will be your answer. :)
For part ii I'm getting negative for a as 1 and as 2
when a = 1
sin(1) - ((1.5-cos(1))/(1)) = -0.118
when a = 2
sin(2) - ((1.5-cos(2))/(2)) = -0.0487
there is no sign change :/
This is in radian mode btw and even in degree mode there is no sign change :S
 
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For part ii I'm getting negative for a as 1 and as 2
when a = 1
sin(1) - ((1.5-cos(1))/(1)) = -0.118
when a = 2
sin(2) - ((1.5-cos(2))/(2)) = -0.0487
there is no sign change :/
This is in radian mode btw and even in degree mode there is no sign change :S
There should beee. Lol, Wait!
 
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Part i is related to part ii here I guess.
So if you let the number of sixes thrown be X
You need to find out the P(X>=4)
Probabiilty of success is 1/6
probability of failure is 5/6
Just use the binomial formula and you'll get the answer.
Thanks!
 
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Just use your answer to part i. If your answer lies between 2 and 3 use 2 as x1 and just keep solving till you get the same answer thrice.
Thats part iii where it asks to use iterative formula to find value of a :p
How to prove that it's converging to a ?
 
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