AP Statistics Ch 3.2

A food server records the total bill and the tip received by 5 individuals who dined alone. Here are the data:

Total: $4.50 $5.79 $6.25 $4.62 $6.35

Tip: $0.75 $1.00 $0.75 $0.58 $1.00

Find the mean of the totals (to the nearest hundredth.)

Tags

CCSS.6.SP.B.5C

A food server records the total bill and the tip received by 5 individuals who dined alone.

The standard deviation of the totals is 0.886 and the standard deviation of the tips is 0.182. r=0.6733

Calculate the slope of the least-squares regression line to the nearest hundredth.

Tags

CCSS.HSS.ID.C.7

A food server records the total bill and the tip received by 5 individuals who dined alone. Here are the data:

Total: $4.50 $5.79 $6.25 $4.62 $6.35

Tip: $0.75 $1.00 $0.75 $0.58 $1.00

Which variable is the response variable?

• The total

• The tip

Tags

CCSS.HSS.ID.C.9

The scatterplot of the totals and tips is described as: There is a weak positive correlation between the total and the tip and there appear to be no unusual points.

What is missing from this description?

• Strength

• Direction

• Unusual Points

• Form

Tags

CCSS.6.SP.B.5C

CCSS.HSS.ID.A.3

A food server records the total bill and the tip received by 5 individuals who dined alone. One customer spent $4.62 on food and left a $0.58 tip.

The LSRL is y^ = 0.0565 + 0.138(total).

Calculate the residual for the $4.62 total (to the nearest hundredth.)

Tags

CCSS.HSS.ID.B.6B

The correlation r between the total bill and the tip received is r^2=0.45. This suggests that:

• total accurately predicts tip.

• tips increase by $0.45 for each additional dollar of total.

• 45% of the relationship between total and tip is accounted for by the regression line.

• about 45% of the variation in tips is accounted for by the least square regression line with x = total bill.

Tags

CCSS.HSS.ID.B.6B

Suppose the tips and the totals were multiplied by 10. How will this conversion affect the value of r^2?

• r^2 will increase

• r^2 will decrease

• r^2 will stay the same

Tags

CCSS.HSS.ID.B.6

CCSS.HSS.ID.C.8

A food server records the total bill and the tip received by 5 individuals who dined alone (and spent between $4 and $7 dollars). The LSRL is y^ = 0.0565 + 0.138(total). Extrapolation would occur if making a prediction based on which of the following bill totals?

• $5.15

• $4.10

• $6.95

• $8.20

Tags

CCSS.8.SP.A.3

Residual plots should...

• have a curved pattern

• be u-shaped

• have random scatter

• appear linear

Tags

CCSS.HSS.ID.B.6B

The standard deviation of the residuals, s, measures...

• the variability of the data

• the size of a typical residual

• the percent reduction on the sum of the squared residuals

• the slope of the LSRL