# Cork and swimming

If a person weighs 80 kg, how many kilograms of cork must take swimming belt to use it to float on water? The density of the human body is 1050kg/m3 and cork 300kg/m3.

(Instructions: Let the human body and cork on a mixture that has a density of 1000kg/m3. When make the equation you will compare the volumes of both components and the volume of the resulting mixture.)

Result

x =  1.633 kg

#### Solution:

80/1050+x/300=(80+x)/1000

49x = 80

x = 80/49 ≈ 1.632653

Calculated by our simple equation calculator.

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