Question 922660
Since we don't know how many coins she has, there are a lot of possibilities.
18.80 = x(.25) + 2x(.10) + NICKELS.... the nickels are the problem because there can be as many as you need.
18.80 = 1(.25) + 2(.10) + 367(.05)
or
18.80 = 41(.25) + 82(.10) +7(.05)
or any number of quarters between 1 and 41.  You could actually use 0 as well, and have all nickels.
Please repost if there is more to the problem.