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Statistics, Confidence Interval

# Statistics, Confidence Interval

I need instructions on how this problem is calculated: 2.575* sqrt (0.333*0.667)/900
Please help. I'm not getting the correct amswer of 0.040 when I enter this on my calculator.

### Comments for Statistics, Confidence Interval

 Dec 05, 2011 Calculations by: Staff Question: I need instructions on how this problem is calculated: 2.575* sqrt (0.333*0.667)/900 Please help. I'm not getting the correct answer of 0.040 when I enter this on my calculator. Answer: The way the problem is written, the answer is 0.0013484, not 0.040. However, if you include two more parentheses so that the problem is written 2.575 * sqrt ((0.333*0.667) / 900), the result is 0.0404521. 2.575 * sqrt (0.333*0.667) / 900 = 2.575 * √(0.333*0.667) / 900 = 2.575 * √(0.222111) / 900 = 2.575 * 0.471287 / 900 = 1.21356 / 900 = 0.0013484 2.575 * sqrt ((0.333*0.667) / 900) = 2.575 * √((0.333*0.667) / 900) = 2.575 * √(0.00024679) = 2.575 * 0.0157096 = 0.0404522 Thanks for writing. Staff www.solving-math-problems.com