Back to Interpret slope and intercept of a linear model — Problem 1 · Task Set 9

Exercises: Interpret the Slope and Intercept of a Linear Model

Work through each section in order. For every interpretation, write a full sentence about the real situation and include UNITS. Remember: the slope is a rate of change (y-units per x-unit) and the intercept is the predicted value when x = 0 (in y-units) — but the intercept is only meaningful when x = 0 is realistic and near the data.

Grade 9·20 problems·~35 min·Common Core Math - HS Statistics and Probability·group·hss-id-c-7

Work through problems with immediate feedback

Fluency Practice

Interpret each slope or intercept as a sentence with units.

$Scatter plot of cost versus minutes with a rising fitted line; a dashed step shows a one-unit increase in x raising y by b.$

The scatter plot below shows a phone bill versus minutes used, with a fitted line $y = a + bx$ . The dashed step shows that moving $1$ unit to the right on $x$ raises $y$ by $b$ . Which is the best interpretation of the slope $b = 0.10$ ?

For each additional minute used, the predicted bill increases by $\text{\char"0024}0.10$ .

The bill is $\text{\char"0024}0.10$ in total.

When $x = 0$ the bill is $\text{\char"0024}0.10$ .

The slope is just $0.10$ with no further meaning.