# Question Video: Calculating the Density of an Object Given Its Mass and Volume Mathematics

True or False: A cylinder with a volume of 1/60 m³ and a mass of 150 kg has a density of 9,000 kg/m³.

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### Video Transcript

True or false: A cylinder with a volume of one sixtieth of a cubic meter and a mass of 150 kilograms has a density of 9,000 kilograms per cubic meter.

We recall that the density of any object is equal to its mass divided by its volume. If the mass is measured in kilograms and the volume in cubic meters, then the units for density will be kilograms per cubic meter. In this question, we are told the cylinder has a mass of 150 kilograms and a volume of one sixtieth of a cubic meter. The density will therefore be equal to 150 divided by one sixtieth. Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. This is sometimes known as KCF. We keep the first number the same, we change the sign to a multiplication, and we flip the fraction.

60 divided by one is equal to 60. So the density is equal to 150 multiplied by 60. 15 multiplied by six is equal to 90. This means that 150 multiplied by 60 is equal to 9,000. The density of the cylinder is 9,000 kilograms per cubic meter. As this is the value we were given in the statement, the correct answer is true. A cylinder with a volume of one sixtieth of a cubic meter and a mass of 150 kilograms will have a density of 9,000 kilograms per cubic meter.