Question 1147131
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Start from


    F = J - 3    (1)    ("Frank  is three years younger than Jack")


From the other side, you are given


    J = 2B + 1   (2)    ("Jack is one year older than twice Ben’s age")


Substitute (2) into (1). You will jet


    F = (2B + 1) - 3,


which is


    F = 2B - 2.        <U>ANSWER</U>
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