A weather balloon holds 2,850 cubic meters of helium. The density of helium is 0.1685 kilograms per cubic meter. How many kilograms of helium does the balloon contain? Please round your answer to the nearest whole number. Only enter a numerical value in the answer blank.

Question

mrnood · Answer

the question tells you that EACH cu metre weighs 0.1685kg

so multiply that by the number of cu meteres in the balloon for your answer

imstuck · Answer

set up a ratio/proportion/equivalency situation where what you are solving for is kilograms.  I teach it like this so it's easy to see how things cancel each other out, etc.
$$2850m ^{3}\times \frac{ .1685k }{ 1m ^{3} }$$

imstuck · Answer

By setting it up like that, you have an equivalency going on between kilograms and cubic meters.  The problem tells you that 1 cubic meter is equal to .1685 kg.  Now the cubic meters cancel each other out, leaving you with 2850 times .1685 with your only label remaining being kg, which is what you're looking for.

thatcreepyboy · Answer

Do I multiply 2,850 by 1685?

thatcreepyboy · Answer

@MrNood  @IMStuck

thatcreepyboy · Answer

Idk....

welshfella · Answer

density = mass / volume 
so plugging in the given values
0.1685  = M /  2850
now multiply  left side by 2850  will give you the mass M.

welshfella · Answer

M = 0.1685 * 2850

use your calculator

thatcreepyboy · Answer

I got 480.225.

thatcreepyboy · Answer

Is it right? Or am I doing something wrong?.

ganeshie8 · Answer

Yes, thats right. You should trust yourself more :)

ganeshie8 · Answer

Hey they want you round the answer to the nearest whole number

ganeshie8 · Answer

What is  480.225 rounded to the nearest whole number ?

thatcreepyboy · Answer

480?

ganeshie8 · Answer

Looks good!

thatcreepyboy · Answer

Thank you! :D