00:02
Hi there.
00:03
In this question, we have a metal cube, and on each edge, since it's a cube, each edge is the same at 7 .23 inches.
00:25
And what we want to do is determine the mass.
00:27
Well, we are given the density in grams per centimeter cube.
00:32
So when i calculate this volume, let's think about the volume.
00:36
Since it's a cube, the volume is going to be length times width times height, but all three of those measurements are the same.
00:43
So in other words, it's just going to be the length cubed.
00:49
So i want this to end up in centimeters cubed.
00:53
So what i want to start off by doing is converting that 7 .23 inches to centimeters.
01:00
We could do it now or we could do it after we cube it, but i'm just going to do it now because i know that in one inch there are 2 .54 centimeters.
01:15
I also know ultimately i'm going to want three significant digits in my answer, but for now i am going to keep some extra significant digits because i don't want to round at each step and make the answer incorrect by rounding at each step.
01:36
Okay, so i just found the 7 .23 inches is 18 .3642 centimeters.
01:42
Again, i did not round significant digits.
01:45
I know ultimately that i will only have three significant digits, but we'll do that at the end...