Imagine you are an engineer who needs to test a scale model of a footbridge. It will be a 1/20 scale model. The footbridge will cross
over a busy road and allow people to cross the road safely. How
could a relatively small design error of 2 centimeters in the model
system cause a significant problem in construction of the bridge?

The problem will be because:

Explanation:

When you, as an engineer, listen about a scale 1/20, it means that for each 1 cm in the model, it will be 20 cm in the real footbridge (20 times upper to the scale model), then how the error in the model is 2 cm, the real error is 40 cm, in this case, imagine that you didn't know that the bridge will have an error of 40 cm, which is approximately 1,31 ft, from a side of the bridge you begin with the correct measure, and the other side you use the measure with the error of the 40 cm, the result is that when you going to finish the bridge in the center, this won't match, making more expenses to correct that big error.

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