If an earthworm is 18 mm long and it is photographed and the picture is magnified 2.5×, how long will it be in the picture?

1. Break Down the Problem

To determine the length of the earthworm in the picture, we need to multiply its actual length by the magnification factor.

2. Relevant Concepts

• Actual length of the earthworm: $L = 18 \text{ mm}$
• Magnification factor: $M = 2.5$

3. Analysis and Detail

To find the length of the earthworm in the picture, we use the formula: $\text{Length in picture} = \text{Actual Length} \times \text{Magnification Factor}$ Now substituting the values: $\text{Length in picture} = 18 \text{ mm} \times 2.5$

4. Verify and Summarize

Now we calculate: $\text{Length in picture} = 18 \times 2.5 = 45 \text{ mm}$ We have verified the calculation, and the length of the earthworm in the photograph is 45 mm.

Final Answer

The length of the earthworm in the picture will be 45 mm.