Answer:
the possible values for the number of nickels that Henry could have are 5, 6, 7, and 8.
Explanation:
Let n be the number of nickels that Henry has.
Since he has 10 dimes, he has $10\cdot 0.10 = $1.00 from his dimes.
Since he needs to have a minimum of $1.25, he needs at least $1.25 - $1.00 = $0.25 from his nickels.
Since each nickel is worth $0.05, he needs at least $0.25/$0.05 = 5 nickels.
Since he has a maximum of 18 coins, he can have at most 18 - 10 = 8 nickels.
Therefore, the possible values for the number of nickels that Henry could have are 5, 6, 7, and 8.