21. Solving a chemistry problem

4.3 A 10 ml wastewater sample containing aluminum is diluted in a 50 ml volumetric flask. To 5 ml of the resulting solution, add 10 ml of aluminone in a buffer solution and dilute to 50 ml. Colorimetric at λ=525 nm. The aluminum content in the sample was 0.05 mg/l. Calculate the aluminum content of the original wastewater solution.