Studying the Probability Model (20 minutes)
Your assessment of students’ progress towards describing the outcomes of the 4-Flip Trip on Day 1 will determine how to proceed on Day 2. On Day 2, examine different aspects of the probability model and work towards drawing conclusions about Flip Trips in general.
Students should discuss why each unique sequence of coin flips in the 4-Flip Trip has 1/16 probability of occurring. Students can imagine that 1000 people are about to take a Flip Trip. Half would flip heads, half tails; of those who flipped heads, half of those would flip heads again, and half tails. Reasoning in this way, students can establish that each different possible sequence of 2 flips has a ¼ probability. A tree diagram representation may be helpful in establishing the equal probabilities of the 16 different outcomes of the 4-Flip Trip.