public interface InterfaceX
{
	public int geek();
}
public interface InterfaceY
{
	public String geek();
}

Now, Suppose we have a class that implements both those interfaces:

public class Testing implements InterfaceX, InterfaceY
{
public String geek()
	{
		return "hello";
	}
}

The question is: Can a java class implement Two interfaces with same methods having an equivalent signature but different return types??
No, its a mistake
If two interfaces contain a way with an equivalent signature but different return types, then it's impossible to implement both the interface simultaneously.
According to JLS (§8.4.2) methods with the same signature aren't allowed during this case.

Two methods or constructors, M and N, have the same signature if they have,
the same name
the same type parameters (if any) (§8.4.4), and
after adopting the formal parameter types of N 
 to the type parameters of M, the same formal parameter types.

It is a compile-time error to declare two methods with override-equivalent signatures in a class.

// JAVA program to illustrate the behavior
// of program when two interfaces having same
// methods and different return-type
interface bishal
{
public
	void show();
}

interface geeks
{
public
	int show();
}

class Test implements bishal, geeks
{
	void show() // Overloaded method based on return type, Error
	{
	}
	int show() // Error
	{
		return 1;
	}
public
	static void main(String args[])
	{
	}
}