WEBVTT
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The scatterplot shows the weights, in kilograms, of students of different heights, in centimeters, in a school.
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According to the line of best fit in the scatterplot, which of the following is the closest approximation of the height of a student whose weight is 75 kilograms?
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A) 158, B) 166, C) 175, or D) 172.
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So in the question, what we need to do is find our approximation for the height of a student whose weight is 75 kilograms.
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And to do that, we’re going to be using the line of best fit.
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And the line of best fit is a line that is drawn on a scatterplot to help us model the trend of the points that have been plotted.
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So we can see that we’ve got the line of best fit here.
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So to make an estimate for the height of a student whose weight is 75 kilograms, I drew a line across from 75 kilograms to our line of best fit.
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And then I drew it down to our 𝑥-axis, which is our height.
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So now what we can do is see which one of our answers is going to be the best approximation.
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So let’s start with 158.
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Well, I’ve marked on 158 approximately on our 𝑥-axis.
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We can see that this is not where the line has come down to.
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So therefore, 158 will not be the correct answer.
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Well then, if we look at answer B), we can see that 166, which I’ve now marked on the 𝑥-axis, is actually pretty close to the line that comes down when we’d go across from 75 kilograms to the line of best fit.
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So this could possibly be our closest approximation.
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Let’s move on to C).
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Well, C) is 175.
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Well, I’ve marked this on our 𝑥-axis.
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And we can see that this is in fact further away.
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So that means that C) is not the correct answer.
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And if we mark on D) — so that’s 172 — again we can see this is a bit closer than 175.
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But this is still further away from our line than 166.
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So this is not the correct answer.
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So therefore, we can say that the answer B) 166 is gonna be the closest approximation for the height of a student whose weight is 75 kilograms.