##### Quiz 6: Second A Level Question
AZobi
You toss a coin 100,000 times. The coin lands on heads exactly 55,000 times. You say that the coin is fair if the probability of heads for the coin is between .49 and .51. Estimate the probability that the coin is not fair?
mtariveran: March 7, 2015, 10:52 p.m.
I got 1-1/[(4)(100000)(0.04)^2]
weisbart: March 8, 2015, 12:47 p.m.
Is the answer exact? What is the estimate?
AZobi: March 8, 2015, 3:53 p.m.
Mtariveran, how did you get 0.04? Shouldn't it be 0.01?
Alan_Mendoza: March 8, 2015, 5:49 p.m.
AZobi, the experimentally determined probability is 0.55 and one of the bounds is 0.51 so that's where the c value of 0.04 comes from. I just have a question on whether or not we have to do anything with the 0.49?
martha2A: March 9, 2015, 1:52 a.m.
I got the same answer as Mtariveran :)
AZobi: March 9, 2015, 2:29 a.m.
That makes sense. Thank you. I got the same answer now :)
SheydaMesgarzadeh: March 9, 2015, 12:08 p.m.
shouldn't we be using the equation p(1-p)/nc^2 instead of 1/4nc^2 because the probability isn't 1/2 as it is in the second B level question?
ANguyen: March 9, 2015, 6:14 p.m.
Weisbart what was the solution?