The figure shows a swimming pool for diving compititons.After filling the swimmng pool with water,the water level is0.2m below the edge of the swimming pool.
a)Find the volume of water in the swimming pool
b)If half of the water is drained away,how far is the water level below the edge of the swimming pool?
[Hint:Let x m be the water level below the edge of the swimming pool.]
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Maths
2008-03-07 6:42 am
回答 (2)
2008-03-07 7:09 am
✔ 最佳答案
(a) Volume of water= {[(5-0.2)+(3.5-0.2)] (20)/2}(20)
= 1620 cu. m.
(b) Half of water drain out
volume remain = 810
The area of the half volume of water occupies
= 810/20 = 40.5 sq. m.
The length of (Left end + Right end)
= 40.5 (2) / 20
= 4.05m
the different between the left end and right end = 5 - 3.5 =1.5m
Let left end be y, right end = y + 1.5
2y + 1.5 = 4.05
2y = 2.55
y = 1.275m
the different between the edge of the swimming pool and water level
= 3.5 - 1.275 = 2.225m
The water level is 2.225m from the edge of swimming pool
2008-03-07 7:01 am
a) 20 x (3.5-0.2 + 5-0.2) x 20/2
= 1620m^3
b) half of the water volume = 1620/2 = 810m^3
Let x be the water level below the edge of the swimming pool
20 (3.5-x + 5 - x) 20/2 = 810
8.5 - 2x = 4.05
2x = 4.45
x = 2.225
= 1620m^3
b) half of the water volume = 1620/2 = 810m^3
Let x be the water level below the edge of the swimming pool
20 (3.5-x + 5 - x) 20/2 = 810
8.5 - 2x = 4.05
2x = 4.45
x = 2.225
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