Final answer:
The correct equation to determine the number of nickels Larry has is 5n + 10(n + 7) = 145, which corresponds to option C.
Step-by-step explanation:
The student is asking how to find the number of nickels Larry has, given that he has 7 more dimes than nickels, for a total of $1.45.
To represent the total value of the coins, we need to remember that each nickel is worth 5 cents (or 0.05 dollars) and each dime is worth 10 cents (or 0.10 dollars). Therefore, the value of the nickels is 5n, since n is the number of nickels, and the value of the dimes is 10(n + 7), since there are n+7 dimes.
Adding these values together should give us the total value of $1.45, which is the same as 145 cents. The correct equation to find n is:
5n + 10(n + 7) = 145
This corresponds to choice C from the provided options, and it correctly represents the value of the nickels and dimes combined, converted into cents to match the total given.