Finding S in a Confidence Interval Estimate for the mean (Standard Deviation Unknown)?

You must find the standard deviation given the 6 data figures. First, find the mean by adding up all the figures given then divide by 6 (Comes out to be 36.53). Now, just find the standard deviation using the formula s = sqrt(((X(bar) - x1)^2 + (X(bar) - x2)^2 + .... + (X(bar) - xN)^2))/(N-1)). Then you should be able to figure out the 95% confidence interval. The standard deviation comes out to be 4.39