Answer:
half of the coins are dimes, and the other half are quarters
Explanation:
Let's use algebra to solve the problem. Let x be the number of dimes and y be the number of quarters. Then, we have:
The number of pennies is 6/2 = 3.
The total value of the coins is 78 cents, so we can write an equation: 3 + 10x + 25y = 78.
We also know that there are no nickels, so x and y must be integers.
To solve for x and y, we can use trial and error. We know that x and y must be positive integers, and 3 + 10x + 25y = 78. Trying different values of x and y, we find that x = 2 and y = 2 are the only solution that satisfy all the conditions. Therefore, half of the coins are dimes, and the other half are quarters.