Linear Extrapolation or Interpolation?

[nycmathguy]

Section 1.3
Question 98

See attachment.

I see two points in the form (t, y):

(1, 970) and (2, 1270)

I need the slope m.

m = (1270 - 970)/(3 - 1)

m = 300/2

m = 150

I need the point-slope formula.

y - y_1 = m(t - t_1)

I need one of the points and m.

y - 970 = 150(t - 1)

y - 970 = 150t - 150

y = 150t - 150 + 970

y = 150t + 820

Part (a) has been completed.

Part (b)

The slope is 150 but I don't know what it tells me about weight gain.

Do you know?

Part (c)

Let t = 2

y = 150(2) + 820

y = 300 + 820

y = 1,220

The average brain weight is 1,220 grams.

You say?

A. Is this a linear extrapolation or linear interpolation?

B. What's the difference between the two mentioned in A?

 

[MathLover1]

(b) The units of the slope here are grams per year, so it tells you the change in brain weight over the change in years.

A. answer is: linear interpolation
Linear Extrapolation
you use data to plot scatter graph, then find the best fitting line
see the below screenshot:

The formula for linear interpolation is slope-point formula

see the below screenshot:

 

[nycmathguy]

(b) The units of the slope here are grams per year, so it tells you the change in brain weight over the change in years.

A. answer is: linear interpolation
Linear Extrapolation
you use data to plot scatter graph, then find the best fitting line
see the below screenshot:

The formula for linear interpolation is slope-point formula

see the below screenshot:

Is my work correct? I say yes.

 

[MathLover1]

Is my work correct? I say yes.

yes, your work is correct

 

[nycmathguy]

yes, your work is correct

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[MathLover1]

I like it here.

 

[nycmathguy]

I like it here.

Ok. We'll stay here. See if you can get more people to join. It's not a bad site.