Using proportions, it is found that an estimated 9.45 million red cars on the road in Britain.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
From Ben's estimate, 27/100 = 0.27 of the cars were red.
Out of 35 million, the amount is given by:
0.27 x 35 = 9.45 million.
More can be learned about proportions at https://brainly.com/question/24372153
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