There must be something missing there is no possible way to answer the question without a variable.
Answer:

Step-by-step explanation:

Step-by-step explanation:
if 9 boxes is 42.75 then 1 box is 4.75 dollars
so 13 boxes would be 13X3.75 which is 61.75$
if 9b=$42.75
1b=x
9bx=$42.75b
x=$42.75b÷9b
x=$4.75
Answer:
36
Step-by-step explanation:
There is no picture of a receipt to see.
but do the cost of food times 0.15 to find out the tip. then do the cost of the food times 1.0875 to find out how much the total would be. then add the tip to the total.
for part B just take the total of everything (previous answer) and divide it by three.