Word Problem...I need an equation

[kjvmen]

I know the answer is four, but I need an equation to prove:

Jim doubled the number of magazine subscrptions he sold each week for four weeks. If he sold 32 subscriptions during the fourth week, how many did he sell the first week?

 

[tkhunny]

I need an equation to prove:

You are missing the point of the exercise. Creating equations is what you should be learning.