According to a CNN report, 93% of Americans also own a traditional phone (not a cell phone). We took a sample of 850 randomly selected Americans and...

According to a CNN report, 93% of Americans also own a traditional phone (not a cell phone). We took a sample of 850 randomly selected Americans and found that 785 of them own a traditional phone.

Use formulas p hat = x/n and z= (p hat - p) / square p(1-p) / n

I just don't know how to find the p value. Can someone explain it to me thank you!