Lesson objective: Apply experimental probabilities to estimate the quantity of each coin, and the total amount of money, in a mystery bag of change.

This lesson provides an opportunity for students to apply their knowledge and understanding of experimental probabilities to a real-life situation. Students are asked to calculate experimental probabilities and use them to estimate how much money is in the bag.

Key Concept students will use:

Skills students will use:

- Calculating experimental probabilities
- Proportional reasoning with percents (Grade 7, Unit 3)
- Rounding (Grade 5, Unit 6)

Students engage in Mathematical Practice 4 (Model with mathematics) as they model a real-world problem of estimating the amount of money in the bag, using experimental probability.

**Key vocabulary: **

- experimental probability
- observations

**Special materials needed:**

- optional: a bag of coins for students to follow up the lesson with their own experiment