# Hot Air Balloon

## Opening

# Hot Air Balloon

Think back to the Hot Air Balloon simulation you worked with earlier in this unit. Then consider the following situation:

Suppose the balloon starts at 0, and you add 2 units of weight to the balloon every minute for 4 minutes. Where will the balloon be after 4 minutes?

Represent this situation in each of the following ways.

- On the number line
- As an addition equation
- As a multiplication equation

## Hint:

- Remember that weight represents a negative number.
- How many units of –2 are added together?
- How can you represent repeated addition as multiplication?
- Each time 2 units of weight are added to the hot air balloon, the balloon's altitude decreases by 2 units.