Answer :
Given:
The scale is 1:250.
To find:
The measurements in metres if 40 mm is drown on the plan.
Solution:
The scale is 1:250. It means,
1 mm of the drawing = 250 mm of original length
40 mm of the drawing = 40×250 mm of original length
40 mm of the drawing = 10000 mm of original length
We know that,
1000 mm = 1 m
1 mm = 0.001 m
10000 mm = 10000×0.001 m
10000 mm = 10 m
Therefore, the measurement is 10 metres if 40 mm is drown on the plan.