PSLE There was a total of 22385 cm
3 of water in rectangular tanks T and U at first. The height of the water level in tank U was 2 cm above that of tank T.
- Find the height of the water level in tank T.
- Min poured 3456 cm3 of water out of tank U. Tank U was then half filled with water. What was the height of tank U?
(a)
Volume of water in Tank U with a height of 2 cm
= 32 x 27 x 2
= 1728 cm
3 Volume of water in both tanks excluding the water that is 2 cm above that of Tank T
= 22385 - 1728
= 20657 cm
3 Base area of Tank T
= 29 x 25
= 725 cm
2 Base area of Tank U
= 32 x 27
= 864 cm
2 Combined base areas of both tanks
= 725 + 864
= 1589 cm
2 Height of water in Tank T
= 20657 ÷ 1589
= 13 cm
(b)
Decrease in the height of Tank U after some water was poured out
= 3456 ÷ 864
= 4 cm
Original height of water before some was poured out
= 13 + 2
= 15 cm
Height of water after some was poured out
= 15 - 4
= 11 cm
Height of Tank T
= 2 x 11
= 22 cm
Answer(s): (a) 13 cm; (b) 22 cm