Math

 

An empty rectangular tank measured 70 cm by 25 cm by 36 cm. A stone volume 4500 cm! is placed in the tank. Then the tank is filled with water flowing from a tap in a rate of 9 liters per minute. How long will it take to fill the tank?     

 

The tank without the stone will hold 70 • 25 • 36 cm³  =  63,000 cm³.     

The stone takes up                                                            4,500 cm³     

Subtract to find that the remaining volume is                   58,500 cm³     

 

A liter is 1,000 cm³ so the tank holds (58,500 / 1000) liters  =  58.5 liters     

 

At 9 liter/min, filling the tank will take (58.5 / 9) minutes        =  6.5 minutes  

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