the number of points issac scores for collecting treasures is Y
Y=100X-50
Calculate the mean and the standard deviation of Y
E[aX+b]=aE[X]+bVar[aX+b]=a2Var[X]E[Y]=E[100X−50]=100E[X]−50Var[Y]=Var[100X−50]=10000Var[X]
I bet you have E[X] and Var[X] from some other part of the problem so plug those in.