90% = mean ± 2.035 SD
2.035 was found by finding table in the back of a statistics text labeled something like "areas under normal distribution" to find the proportion (.45) between score and mean to get the Z score (value in terms of standard deviation).
You measure 34 turtles' weights, and find they have a mean weight of 66 ounces. Assume the population standard deviation is 9.3 ounces. Based on this, construct a 90% confidence interval for the true population mean turtle weight.
Give your answers as decimals, to two places
1 answer