You should Z value.
20 independent observations on a random variable X with unknown distribution function F(x) are:
142 134 98 119 131 103 154 122 93 137 86 119 161 144 158 165 81 117 128 103. find the 95% confidence interval for F(100).
my working:
i found that the sum of all 20 numbers are 2595. hence sample mean is 124.75.
after that what should i do?
thanks
i think that there might be another way to do it because in usual cases, the confidence intervals are values around the the sample mean... however in this question, the confidence interval is very small..which makes me wonder why this is such the case..