Hey, I've been trying to calculate the mean from a set of measurements I took in an experiment. The measurements are (76.0,75.9,76.1,75.9,76.0,76.1,76.1,76.0,75.9,76.0,76.0,75.9,75.9,75.9,76.0,75.8,76.0,76.0,75.9,75.9,75.9,75.9,75.9,75.9,75.9,76.0,75.9,76.0,76.0,76.0), and I always do

y1:=(all of the measurements I just listed);

then I try to do the mean of y1

Mean(y1);

but everytime I try this an error comes up. 

Error, (in Statistics:-Mean...