Inequalities help with word problem

Suppose you want to cover the back yard with decorative rock and plants and some trees. I need 30 tons of rock to cover the area. If each ton cost $60 and each tree is $84, what is the maximum number of trees you can buy with a budget for rocks and trees of $2,500? Write and inequality that illustrates the problem and solve. Express your answer as an inequality and explain how you arrived at your answer.

Now, I can do most of this by doing basic math. I know that 30 tons of rock at 60 dollars a ton is $1800 total. I subtracted the $1800 from the $2500 and I have $700 left for trees. Trees being $84 dollars each I know that I can only by 8 trees for a total cost of $672 dollars. But I am so lost as to writing this as an inequality.

I thought inequality symbols were greater than or less than or greater than or equal to or less than or equal to.

I'm a bit confused as to how to write this problem as an inequality.

Im asked if 5 would be the solution to the inequality and I know that it wont because 5 does not get me close to the 700 mark for trees.

Im just a bit lost here.