Find the rejected region in the problem of a biased die - Hypothesis

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The discussion focuses on calculating the probability of a biased die, specifically how to determine P(X≥10) using the formula P(X≥10) = 1 - P(X≤9). Participants analyze a similar problem to validate their approach, confirming that the method involves summing probabilities for values less than or equal to a certain threshold. Clarity is sought on whether this method is the most efficient for the original problem. The consensus is that while the method is correct, it requires extensive calculations, highlighting the computational burden on students.
chwala
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Homework Statement
Kindly see attached question and mark scheme guide
Relevant Equations
##Bin (n,p)##
Consider the question below:

1626846377308.png


this (below) is the mark scheme for the problem, there were different methods given in the mark scheme but i was interested on this one only...

1626846432252.png


Now onto my question, How did they calculate ##P(X≥10)##=##1-P(X≤9)##=##0.055##...?

In attempting to understand the question i went ahead and looked at a similar problem (attached below); i.e

1626846784214.png


and i could see from my analysis that, the highlighted value could have been found using the steps below:
##P(x≥4)=1- [ P(x=0) +P(x=1)+P(x=2)+P(x=3)]##
=## 1- [0.1615+0.3230+0.2907+0.1550]##
=##1-0.9302##
=##0.0698##
ok is this correct? if so going back to our problem, do we use the same approach? or there is a shorter way...
This is the only part that i need clarity. I should be able to come to the deduction on whether to reject or accept null hypothesis.
 
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Yes, this is the way to compute it.
 
Orodruin said:
Yes, this is the way to compute it.
Thanks, implying that a student would have a lot of computation work to do (with calculator) to realize ##P(X≥10)## and ##P(X≥11)##... and then come to some conclusion... Phew!
 
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