Answer
The mean is 50.36, no mode, the median is 73, the midrange is 48.5.
Work Step by Step
The mean can be counted by summing all the data and dividing it by the number of data: $\frac{9+23+25+88+12+19+74+77+76+73+78}{11}=50.36$, the mean is 50.36. The mode is the data occuring the most times but here all data occurs one time, therefore there is no mode. The median is the average of the 1 or 2 (here 1) middle data: (73)/1=73, the median is 73. The midrange is the average of the highest and the lowest data: (9+88)/2=48.5, the midrange is 48.5. It does npt make sense to calculate these because the shirt numbers do not have a numerical value.