Question

The table shows how the lengths of four pet lizards are changing over time. Time (years) Lizard Name and Length (centimeters) Chuck Betty Snapper Rocky 0 9 7 12 11 1 10 8 14 14 2 12 10 17 17 3 16 13 19 20 4 24 17 22 23 Which lizard is growing at a constant rate? A. Chuck B. Betty C. Snapper D. Rocky

Answer 1

To determine which lizard is growing at a constant rate, we need to look at the change in length for each lizard over the years.

Let's calculate the change in length for each lizard year by year:

- **Chuck**:
- Year 0 to Year 1: 10 - 9 = 1 cm
- Year 1 to Year 2: 12 - 10 = 2 cm
- Year 2 to Year 3: 16 - 12 = 4 cm
- Year 3 to Year 4: 24 - 16 = 8 cm
- **Growth is not constant.**

- **Betty**:
- Year 0 to Year 1: 8 - 7 = 1 cm
- Year 1 to Year 2: 10 - 8 = 2 cm
- Year 2 to Year 3: 13 - 10 = 3 cm
- Year 3 to Year 4: 17 - 13 = 4 cm
- **Growth is not constant.**

- **Snapper**:
- Year 0 to Year 1: 14 - 12 = 2 cm
- Year 1 to Year 2: 17 - 14 = 3 cm
- Year 2 to Year 3: 19 - 17 = 2 cm
- Year 3 to Year 4: 22 - 19 = 3 cm
- **Growth is not constant.**

- **Rocky**:
- Year 0 to Year 1: 14 - 11 = 3 cm
- Year 1 to Year 2: 17 - 14 = 3 cm
- Year 2 to Year 3: 20 - 17 = 3 cm
- Year 3 to Year 4: 23 - 20 = 3 cm
- **Growth is constant (3 cm each year).**

Based on these calculations, the lizard that is growing at a constant rate is **D. Rocky**.