PSLE
There was a total of 24004 cm³ of water in rectangular tanks V and W at first. The height of the water level in tank W was 2 cm above that of tank V.

1. Find the height of the water level in tank V.
2. Emily poured 4080 cm³ of water out of tank W. Tank W was then half filled with water. What was the height of tank W?

(a)
Volume of water in Tank W with a height of 2 cm
= 34 x 24 x 2
= 1632 cm³

Volume of water in both tanks excluding the water that is 2 cm above that of Tank V
= 24004 - 1632
= 22372 cm³

Base area of Tank V
= 25 x 20
= 500 cm²

Base area of Tank W
= 34 x 24
= 816 cm²

Combined base areas of both tanks
= 500 + 816
= 1316 cm²

Height of water in Tank V 
= 22372 ÷ 1316
= 17 cm

(b)
Decrease in the height of Tank W after some water was poured out 
= 4080 ÷ 816
= 5 cm

Original height of water before some was poured out
= 17 + 2
= 19 cm

Height of water after some was poured out
= 19 - 5
= 14 cm

Height of Tank V
= 2 x 14
= 28 cm

Answer(s): (a) 17 cm; (b) 28 cm