This is the In/Out table I've been given:
In|Out
3|8
5|12
9|20
15|32
X|?
Should the bottom of the In/Out table be 2(X + 1) OR 2X + 2? Or are both equations correct? Or are neither correct? This is a problem I'm not sure about. 2X + 2 seems to work but I'm not sure about the other one. Thanks for your advice.