Question 8b

"A tank measuring 45 cm by 24 cm and 27 cm was 1/3 filled with water at first."

so that means the water that is not filled in fractions → 1 - 1/3 = 2/3

2/3 volume (water not filled in) → 2/3 x length x breadth x height = 2/3 x 45 x 24 x 27 = 19440 cm³
= 19.44 litres

"Dillon turned on a tap and let water flow into the tank at a rate of 1.35 l per minute. After 15 minutes, he turned off the tap."

tap water flowed in → 1.35 x 15 = 20.25 litres

water overflowed → tap water flowed in - water not filled in = 20.25 - 19.44 = 0.81 litres