00:02
Hi there.
00:03
In this question, we have actually two questions.
00:06
We have question four, followed by question five.
00:09
So let's start with number four.
00:11
Number four, we have a calculation to do.
00:16
We are multiplying 81 .04 times 0 .010.
00:26
And we need to report our answer to the correct number of significant digits.
00:32
Okay, so when we are multiplying or dividing, we have to round our answer to the same number of significant figures as the value that had the fewest significant figures.
00:45
So in other words, as we look at 81 .04, that has four significant figures.
00:52
All of those numbers are significant.
00:55
So four significant figures.
01:00
0 .010 only has two significant figures.
01:05
Those first two zeros are just placeholders, the one, and the zero that follows it are part of the measurement.
01:12
So this has two significant figures.
01:15
So that means our answer has to be rounded to two significant figures.
01:21
So first we just need to go ahead and multiply this together.
01:24
And our calculator gives us 0 .8104.
01:30
But we need to round this to just two significant figures.
01:34
So that means just the eight and the one.
01:37
We look after the one and the next digit is a zero, so we are not going to round that one upward.
01:44
So we just need to report our answer to two significant digits, which is going to be 0 .81.
01:51
So 0 .81 is the correct answer.
01:54
And this looks like the third answer choice there, your third answer option.
02:06
All right.
02:07
Let's move on to the next question.
02:09
In the next question, we are trying to purchase 17 apples.
02:15
So 17 is a counting number.
02:17
It does not have significant digits...