I have to figure out what to missing data points are from a set of 10 scores. The mean of the 10 observed scores is 20.0 and the standard deviation is 6.0. The observed scores are listed below, with the two missing scores shown as a blanks. What formula/method do I use to determine these scores? We learned basic standard deviation calculations in class but I can't figure out how to reverse it to find these two scores.
{13, 11, 20, 24, 29, 27, 16, 20, _, _ }