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1 of 8 0-day streak

Compute r and the least-squares line from data

DIFFICULTYintrostandardchallengeexam
QUESTION TYPEMix of allChange
Equation; strong positive; EV firstEquation; strong negative; EV firstNOWMix of allRecommended
Question 1 of 8

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The aim is to predict stream inflow from rainfall. Use technology with the data below

rainfall (mm)stream inflow (ML)
23261
26265
28265
31301
33309
36297
38313
41333
Scatterplot with 8 points. The horizontal axis is rainfall (mm) and the vertical axis is stream inflow (ML). The observed rainfall values run from 23 to 41, and the observed stream inflow values run from 261 to 333. The plotted response values generally increase as the explanatory values increase.3040260280300320340rainfall (mm)stream inflow (ML)
(a)1 mark

Identify the variable that technology should treat as x

(b)2 marks

Report a and b for the regression that predicts stream inflow. Give both values to 2 decimal places

Use the form: predicted stream inflow = a + b × rainfall