I like to know the steps to this type of question please and thank you

In this problem they are telling you that the mean is 64 ounces and that the standar derivation is 2.4 onces so:
To find the maximun value that can have Mu we have tu sum the standart derivation to the mean so:
[tex]\text{maximun}=64+2.4=66.4[/tex]and to calculate the minumun value that can have mu we rest the standar derivation from the mean so:
[tex]\text{minumun}=64-2.4=61.6[/tex]so the solution is:
[tex]61.6<\mu<66.4[/tex]