Final answer:
Benjamin's total number of coins is the sum of the dimes and quarters he has. If he has 11 dimes and 7 quarters, he has a total of 18 coins. For a variable number of dimes (d) and quarters (q), the expression for the total is d + q.
Step-by-step explanation:
The question asks how many coins Benjamin has if he has d dimes and q quarters.
To calculate the total number of coins, we simply add the number of dimes to the number of quarters.
Therefore, the expression for the total number of coins Benjamin has would be d + q.
If Benjamin has 11 dimes and 7 quarters, we would calculate the total as 11 + 7 to get 18 coins in total.