Helping math teachers bring statistics to life
Learning Targets

Find and interpret conditional probabilities using twoway tables.

Use the conditional probability formula to calculate probabilities.

Determine whether two events are independent.
Quiz 12.3
Chapter 12  Day 4
Students Struggled With…

Remembering what needed to be checked for each of the five conditions.

Understanding the difference between a residual plot and a dotplot of the residuals.

Mixing up the slope and yintercept from computer output.
Remedies…

(Condition)  how to check it > SO WHAT?

(Linear)  scatterplot linear or residual plot with no leftover pattern > so there is a fairly linear relationship between x and the mean of y.

(Independent)  10% condition > so sampling without replacement is OK

(Normal)  dotplot of residuals is approximately normal > so for each x, the distribution of y is approximately normal.

(Equal Variance)  residual plot shows similar size residuals for each xvalue > so for each x, the standard deviation of y is the same.

(Random)  random sample or random assignment > so we can generalize to the population or we can show causation.

Remind students that statisticians use y = a + bx rather than y = mx + b. It makes sense that the computer output would give us the yintercept first. hey should calculate a zscore and find the area above it.