for subView in self.pageVC.view.subviews {
    if let subView = subView as? UIScrollView {
        subView.delegate = self
    }
}

func scrollViewDidScroll(_ scrollView: UIScrollView) {

    debugPrint("offset : (scrollView.contentOffset.x)")
    let x = (1/3) * (scrollView.contentOffset.x) - 1
    debugPrint("X val :(x)")
}