After earning interest, the balance of an account is $420. The new balance is 7/6bof the original balance. Write an equation that can be used to find the original balance b of the account.
Well, we know that the total amount is $420, so we can already set one side of the equation. =420. Also, it said that the $420 is (equal to) 7/6b (b for balance). Now just put it together! 7/6b=420 is your answer.