This book is popular with my male friends. Therefore, I think you, as a guy, will probably like it as well.

Is the argument above inductive or deductive? Why?

I believe that the answer is deductive reasoning because this statement goes from a general case (this book is popular with my male friends.) to a specific instance (i think you as a guy will probably like it as well)

Where as inductive goes from a specific case to a broad statement

It is deductive since deductive reasoning is a type of logic where general statements, or premises, are used to form a specific conclusion. Since the person assumed your liking based on past reasoning, it is deductive. An example of this would be all men are mortal. Joe is a man. Therefore Joe is mortal