An aquarium took 96 minutes to completely fill with water. Water was filling the aquarium at a rate of 25 litres every 2 minutes. Given that the aquarium was 2 m long and 80 cm wide, compute the height of the aquarium.

Let height of aquarium be h cm.

Volume of aquarium = l × b × h

= 2 m × 80 cm × h cm

= 200 cm × 80 cm × h cm

= 16000h cm³

= $\dfrac{16000\text{h}}{1000}$ litres

= 16h litres.

Given,

Water was filling the aquarium at a rate of 25 litres every 2 minutes i.e., 12.5 litres per minute.

So, in 96 minutes, water filled = 96 × 12.5 = 1200 litres.

So, volume of aquarium = 1200 litres.

∴ 16h = 1200

h = $\dfrac{1200}{16}$ = 75 cm.

Hence, height of aquarium = 75 cm.