Question

Politicians are interested in knowing the opinions of their constituents on important issues. One administrative assistant to a senator claims that more than 63% of adult women favor stricter gun laws. A recent telephone survey of 1026 adult women by IBR Polls found that 65.9% of adult women favored stricter gun laws.

The 90% confidence interval is: ( % , %)

Enter each number as a percent rounded to tenths of a percent.

I got 63.5 to 68.3. Is my answer correct?

Answer 1

n = 1026
za/2 = 1.645

phat = .659

qhat = 1-phat

qhat = 1-.659 = .341

Error = z/2* sqrt( phat *qhat/n)

E = 1.645 * sqrt(.659 * .341/1026))

E = 0.0243

Phat -E <p< phat + E

(.659-.0243, .659+ .0243)

(.6347, .6833) or ( 63.5% , 68.3%)

The 90% confidence interval is : (63.5%, 68.3%)

Answer 2

Is the p-value 0.4995?