comment on the statement "the mean loss for customers at first state bank (which was not insured) was $150 the standard deviation of the losses was -125?

Here the mean of the customers loss is $150, i.e. $150 per
customer on an average.

Now the standard
deviation can be calculated as:

Here the standard
deviation is -$125. Or it can be said
that the standard deviation is + 125.

This means all the values have a variation of about 125$
from the mean value.

Please let me know if you need any clarification for the doubts. I'm always happy to answer your questions. Looking forward to help you again. thank you. :)