Thread: p (density) = m (mass)/V (volume) problem

I know that p=m/v but I still have no idea how to answer this word problem:

"b) Calculate the density of a mixture of 40% antifreeze and 60% water, if there is a 5% decrease in total volume when they are mixed."

and just in case this question needs the previous question since they are both part of the same number, here is the previous question (which I figured out how to do):

"a) Calculate the mass of a four-litre jug of antifreeze (ignore the mass of the plastic container) if the density of antifreeze is 800 kb/m^3."

consider mixing 40 m^3 of antifreez and 60 m^3 of water.

Mass of resultant mixure = 40 x 800 + 60 x 1000 (considering density of water as 1000k/m^3 .check it)
= 92000

Volume of resultant mixure = 100 - 5 = 95 (since there is decrese of 5% volume)

density = m/v
= 92000/95 Answewr

Originally Posted by arpitagarwal82

consider mixing 40 m^3 of antifreez and 60 m^3 of water.

Mass of resultant mixure = 40 x 800 + 60 x 1000 (considering density of water as 1000k/m^3 .check it)
= 92000

Volume of resultant mixure = 100 - 5 = 95 (since there is decrese of 5% volume)

density = m/v
= 92000/95 Answewr

How did you get m^3 out of %?

mixture has 40% AF and 60& water.
so every 100 m^3 has 40 m^3 AF and 60 m^3 water.

Originally Posted by arpitagarwal82

mixture has 40% AF and 60& water.
so every 100 m^3 has 40 m^3 AF and 60 m^3 water.

So it could have been like every 1000m^3 has 400m^3 of Antifreeze and 600m^3 of water?

Originally Posted by s3a

So it could have been like every 1000m^3 has 400m^3 of Antifreeze and 600m^3 of water?

yes