PSLE There was a total of 39070 cm
3 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.
- Find the height of the water level in tank V.
- Jean poured 6090 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
= 35 x 29 x 2
= 2030 cm
3 Volume of water in both tanks excluding the water that is 2 cm above that of Tank V
= 39070 - 2030
= 37040 cm
3 Base area of Tank V
= 31 x 27
= 837 cm
2 Base area of Tank W
= 35 x 29
= 1015 cm
2 Combined base areas of both tanks
= 837 + 1015
= 1852 cm
2 Height of water in Tank V
= 37040 ÷ 1852
= 20 cm
(b)
Decrease in the height of Tank W after some water was poured out
= 6090 ÷ 1015
= 6 cm
Original height of water before some was poured out
= 20 + 2
= 22 cm
Height of water after some was poured out
= 22 - 6
= 16 cm
Height of Tank V
= 2 x 16
= 32 cm
Answer(s): (a) 20 cm; (b) 32 cm