Calculate the number scale of a store layout plan given the actual width is 4 m and assuming the drawn width is 2 cm.

The actual width of Store Z is $4 \text{ m}$.

To derive the number scale, the width of Store Z on the layout plan must be measured from a physical copy. Since I cannot physically measure the image, I will assume that the width of Store Z on a printed version of the plan measures $2 \text{ cm}$.

Convert the actual width to centimeters so it is in the same unit as the assumed drawn width:

The number scale is the ratio of the drawn width to the actual width:

This means that $1 \text{ cm}$ on the plan represents $200 \text{ cm}$ (or $2 \text{ m}$) in reality.

The number scale used to draw this layout plan is $\text{1:200}$.