We will call the amount of each candy as X and Y.
Candy X sells for $1.20 per pound.
Candy Y sells for $2.00 per pound.
The total mix weights 26 pounds, so we can write:

Then, the final price of the mix will be 26 pounds * 1.65 $/pound = $42.9. This final price is equal to the sum of X by its price and Y by its price:

Now we have a system of equations with two unknowns.
We can replace X in the second equation knowing that:


With the value of Y, we can calculate X as:

Answer:
The amount of the $1.20 candy is 11.38 pounds and the amount of the $2 candy is 14.62 pounds.