Ashley has some pennies and some nickels. She has at most 22 coins worth a minimum of $0.78 combined. If Ashley has 4 pennies, determine the minimum number of nickels that she could have. If there are no possible solutions, submit an empty answer.

18 nickels

Step-by-step explanation:

4 pennies = $0.04. 22 coins minus the 4 pennies = 18. So, 18 nickels is equal to $0.90. Because she has at most 22 coins and they're worth at least $0.78 then $0.94 would make since.

The minimum number of nickels that she could have is 15

Step-by-step explanation:

Let x represent the number of nickels Ashley has. If she has 4 pennies and has at most 22 coins, then

→ x + 4 < = 22

→ x < = 18 (1)

Her coins worth a minimum $0.78. Also, it is known that 1 dollar is equal to 100 cents and 1 nickel is equal to 5 cents.

→ (x * 5) + 4 > = 78

→ 5x > = 74

→ x > = 14.8 (2)

If we combine the equation 1 and 2:

14.8 < = x < = 18

The minimum value of x is 15