VTMO 2021 — Grade 5 — cup Question 7

Tank base $48 dm^{2}$, initial water depth $6 dm$. Tap A adds $32$ liters/minute and $B$ drains $18$. After $36$ minutes the water reaches $\frac{3}{4}$ of the tank height. Find tank height; $1$ liter $= 1 dm^{3}$.