The scale from the actual coin to the photo is 8 mm to 2 cm. In the photo, the distance across the coin is 3.25 cm. What is the distance across the actual coin?

13 mm

Step-by-step explanation:

Given that scale from actual coin to the photo is

8 mm to 2 cm.

Distance across the coin in photo  is 3.25 cm.

To find:

Distance across the actual coin = ?

Solution:

First of all, let us learn about scaling concept.

The concept of scaling is used to represent the actual object as as image so that it can be drawn on a paper.

This scaling can result in a smaller image or a bigger image depending upon the size of object.

Here, 8 mm coin is represented as 2 cm coin on the photo.

Let us use unitary method to identify the distance across actual coin to the distance across photo.

2 cm ---- 8 mm

1 cm ------

3.25 cm ------- 4 \times 3.25 mm = 13 mm