What proportion could be used to find the missing length?

Answerthe simplified expression isexplanationthe given expression is,let us deal with the bracket first.the two negatives in the parenthesis will become positive.the expression now becomes,we now expand the parenthesis to get,we group like terms to obtain,this simplifies to,

There is 240 red cars and there is 400 blue cars because 240/3=80 and 80*5=400