How much money does a typical family of four spend at McDonald’s restaurants per visit? The amount is a normally distributed random variable whose mean is $16.40 and whose standard deviation is $2.75....

How much money does a typical family of four spend at McDonald’s restaurants per visit? The amount is a normally distributed random variable whose mean is $16.40 and whose standard deviation is $2.75.

Find the probability a family of four spends less than $10.

What is the amount below which only 10% of families of four spend at McDonald’s?