Answer:
23 dimes, 32 nickels
Step-by-step explanation:
Let n equal the number of nickels and d be the number of dimes. We can use the information given to create a system of equations, as follows:
The total number of coins (the number of nickels plus the number of dimes) is 55, giving us the equation n + d = 55.
The total amount is $3.90. Since each nickel is worth $0.05 and each dime is worth $0.10, we get the equation 0.05n + 0.10d = 3.90.
Multiplying the second equation by 20, we get n + 2d = 78. We can subtract the first equation to get d = 23. Substituting this into the first equation, we get that n = 32.
Therefore, there are 23 dimes and 32 nickels.
