Ihave exactly 12 coins in my pocket worth exactly $1.00. i might have nickels, dimes, and/or quarters. what combination of coins might i have? find all possibilities.

10 pennies and 9 dimes = $1

18 nickels and 1 dime = $1

15 pennies, 1 dime, and 3 quarters = $1

10 pennies, 8 nickels, and 1 half dollar = $1

5 pennies, 9 nickels, and 5 dimes = $1

15 pennies, 2 nickels, 1 quarter, and 1 half dollar = $1

10 pennies, 3 nickels, 5 dimes, and 1 quarter = $1

10 pennies, 6 nickels, 1 dime, and 2 quarters = $1

5 pennies, 12 nickels, 1 dime, and 1 quarter = $1

what i would say the best answer is a. 40.5