PSLE There was a total of 41352 cm
3 of water in rectangular tanks W and X at first. The height of the water level in tank X was 2 cm above that of tank W.
- Find the height of the water level in tank W.
- Eva poured 3108 cm3 of water out of tank X. Tank X was then half filled with water. What was the height of tank X?
(a)
Volume of water in Tank X with a height of 2 cm
= 37 x 28 x 2
= 2072 cm
3 Volume of water in both tanks excluding the water that is 2 cm above that of Tank W
= 41352 - 2072
= 39280 cm
3 Base area of Tank W
= 32 x 29
= 928 cm
2 Base area of Tank X
= 37 x 28
= 1036 cm
2 Combined base areas of both tanks
= 928 + 1036
= 1964 cm
2 Height of water in Tank W
= 39280 ÷ 1964
= 20 cm
(b)
Decrease in the height of Tank X after some water was poured out
= 3108 ÷ 1036
= 3 cm
Original height of water before some was poured out
= 20 + 2
= 22 cm
Height of water after some was poured out
= 22 - 3
= 19 cm
Height of Tank W
= 2 x 19
= 38 cm
Answer(s): (a) 20 cm; (b) 38 cm