Question 153128
I am the dad here and frustrated I can't help my son with this problem. It reads: If 1.0 km cubed of air has mass 1,200,000,000 kg, what is the density of air in g/cm cubed? 
:
1,200,000,000 = 1.2(10^9)
:
Convert the mass: 1.2(10^9) kg to grams:
1.2(10^9) * 10^3 = 1.2(10^12) grams
:
To convert 1 cu km to cubic cm
First:
1 km = 10^3 meters = 10^5 cm
then
Find the volume of a cube with sides of 10^5 cm: (10^5)^3 = 10^15 cu/cm
:
Dens = {{{(1.2(10^12))/(10^15)}}} = {{{1.2(10^((12-15)))}}} = {{{1.2(10^-3)}}} grams/cu cm
;
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