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really need help

please like if hard question

don't think anyone can answer this???

prize for who answers this: i will like all your posts.

ask CPhill i liked his posts.

lynx7
Nov 18, 2017

#1**+3 **

volume of water removed in 30 minutes = 2m * 1m * 20cm

volume of water removed in 30 minutes = 2m * 1m * 0.2m

volume of water removed in 30 minutes = 0.4 m^{3}

So the pump removes water at a rate of 0.4 m^{3} per 30 minutes.

That is 0.8 m^{3} per hour.

volume of pond = area of trapezoid base * height

volume of pond = (1.4m + 0.6m) / 2 * 2m * 1m

volume of pond = 2 m^{3}

2 m^{3} / 0.8 m^{3} = 2.5

So he has to wait 2.5 hours total for the pond to completely empty.

That is 60 + 60 + 30 minutes, or 150 minutes .

hectictar
Nov 18, 2017

#1**+3 **

Best Answer

volume of water removed in 30 minutes = 2m * 1m * 20cm

volume of water removed in 30 minutes = 2m * 1m * 0.2m

volume of water removed in 30 minutes = 0.4 m^{3}

So the pump removes water at a rate of 0.4 m^{3} per 30 minutes.

That is 0.8 m^{3} per hour.

volume of pond = area of trapezoid base * height

volume of pond = (1.4m + 0.6m) / 2 * 2m * 1m

volume of pond = 2 m^{3}

2 m^{3} / 0.8 m^{3} = 2.5

So he has to wait 2.5 hours total for the pond to completely empty.

That is 60 + 60 + 30 minutes, or 150 minutes .

hectictar
Nov 18, 2017