 So now we're going to go over a calculation with significant figures. So notice what kind of operations, mathematical operations are we doing in this problem? Addition. Yeah, just addition, okay? So we have to just use the addition-subtraction rules, okay? So if you recall, does anybody recall what we have to do in addition-subtraction? Align the decimal. Very good. Yes, align the decimal. So the best way to do it, I think, is to put them on top of each other, okay? So you can see where the decimal point is and what tens, hundreds, or whatever unit to go to after your calculation is over. So five, zero. And they're all grams, okay? So our addition-subtraction rules tells us what to go to the one that has the least number after the decimal, okay? So the least number of significant figures after the decimal. Is everybody okay with that? So we would cut it off right there, okay? Like that. Okay, so let's add this up. So I'm going to do this on my calculator. 106.7 plus 0.25 plus 0.195. Okay, when I do that, I get this number. 107.145. 145. Okay? So do we keep this 4.5 in this answer? You guys remember? Well, yeah, we're going to round. So are we going to keep that 4.5 or are we going to round that one, right? Okay. So are we going to round that one down or up in this case? Down. Down, right? Because four is below five. And we've got to remember our units. So what's our final answer going to be over here? 107.1. Okay, so very important to put the units there. Okay, so is everybody okay with doing an addition report? You would use the same rules for subtraction, okay? So any questions on this one? Wonderful.