A supplier sellers 2 1/4 pounds of mulch for every 1 1/3 pounds of gravel. The supplier sells 172 pounds of mulch and gravel combined. How many pounds of each item does the supplier sell?

Answer 1

If there are x lbs of mulch, then the rest (172-x) is gravel.
So,
2 1/4 * x + 1 1/3 (172-x) = 172

Now just find x