Final answer:
Dillon's total cost after a 10% tip on his haircut, originally costing x dollars, is correctly represented by the expression 1.1x. This is because a 10% tip adds on to the original price, resulting in an increase of 10% of the initial amount.
Step-by-step explanation:
The student question revolves around the concept of calculating the total cost of a service including a percentage-based tip. When Dillon pays x dollars for a haircut and gives a 10% tip, his total cost would be the sum of the original price (x) plus the amount of the tip (0.1x). Therefore, the expression representing his total cost would be x (the cost of the haircut) plus 0.1x (the tip), which simplifies to 1.1x.
To illustrate this with an example, let's say your wage is $10 per hour and you receive a $2 raise, making your new wage $12 per hour. The percentage increase in your pay is 20%, because $2 is 20% of $10. Similarly, adding a 10% tip to the cost of a haircut equates to a 10% increase in the total cost. So, the correct answer to the student's question would be option B: 1.1x.