This is an application of linear equations in two variables
Let c = candies(in pounds) ; m = mints(in pounds also)
From this sentence >> 3 pounds of candy and 2 pounds of mints cost $10.80
you can make-up an equation >> 3c + 2m = 10.80 right?
That's your first equation, 3c + 2m = 10.80 ... (1)
and from this sentence >> 1 pound of candy and 3 pounds of mints cost $5.35
you can make-up an equation >> c + 3m = 5.35 ... (2)
you can use various methods here, like graphing, substitution, comparison, and elimination method.
Let's try using substitution method.
3c + 2m = 10.80 ... (1)
c + 3m = 5.35 ... (2) << here you can come up with c = 5.35 - 3m then substitute it to (1)
3c + 2m = 10.80 ... (1)
3(5.35 - 3m) + 2m = 10.80
16.05 - 9m + 2m = 10.80
-7m = -5.25
m = 0.75 <<This is the price of the mint
to get the price of candy, simply substitute m = 0.75 to (1) or (2) if you want, it depends on you.
Either way, you will have the same answer.
Let's try substituting in (1)
3c + 2m = 10.80 ... (1)
3c + 2(0.75) = 10.80
3c + 1.5 = 10.80
3c = 9.3
c = 3.1 <<this is the price of the candy