Jessica's bank contains 18 quarters and dimes, of which q are quarters. Find the total value of the coins in dollars.

To find the total value of the coins in dollars, we need to determine the value of each type of coin (quarter and dime) and then calculate the sum.

Let's start with the quarters:

We know that there are 18 quarters and we need to find the value of each quarter. The value of a single quarter is 25 cents or $0.25.

Therefore, the total value of the quarters can be calculated by multiplying the number of quarters (q) by the value of each quarter. So, the value of the quarters would be q * $0.25.

Now let's move on to the dimes:

Since there are a total of 18 quarters and dimes, we can find the number of dimes by subtracting the number of quarters (q) from the total number of coins (18 - q). Therefore, the number of dimes would be (18 - q).

The value of a single dime is 10 cents or $0.10.

Similar to the quarters, the total value of the dimes can be calculated by multiplying the number of dimes (18 - q) by the value of each dime. So, the value of the dimes would be (18 - q) * $0.10.

Finally, we can calculate the total value of the coins by adding the value of the quarters (q * $0.25) to the value of the dimes ((18 - q) * $0.10).

Total value of the coins in dollars = (q * $0.25) + ((18 - q) * $0.10)