Suppose that prior to conducting a coin-flipping experiment, we suspect that the coin is fair. how many times would we have to flip the coin in order to obtain a 90% confidence interval of width of at most .18 for the probability of flipping a head? a) 83b) 84c) 87d) 50e) 51f) none of the above

 b) 84

Step-by-step explanation:

Let p be the prior estimate of the required proportion.

As per given , we have

p =0.5   (The probability of getting heads on a fair coin is 0.5)

Significance level :

Critical z-value (using z-value table ) :

Confidence interval width : w= 0.18

Thus , the margin of error :

Formula to find the sample size ( if prior estimate of proportion is known.):-

Substitute the values , we get

Simplify ,

 [Round of to the next whole number.]

Hence, the number of times we would have to flip the coin =84

hence, the correct answer is b) 84

these sign is used to tell weather the number is greater or less than the number   <   or >     but this sign means its equal =    

hope this you and

step-by-step explanation: