please solve this summation of indexed data. please read it thoroughly. no one has yet to get these right

The following is a list of 14 measurements -3. -53, 17. -1, 53, -75, -22, 16, 14, 91, 64, 1. 38, -61 Send data tin calculator Send data to Excel Suppose that these 14 managements are respectively labeled X,,. .... X- (Thus, -3 is leleled x]. -53 to labeled I,, and so on) Compute the folowing 1- Round your answer to el least two decimal places. x 5