Hi @Gana_Dube
Yes, this is an acceptable way to show the value of lbl_4 in the second screen.
The comment I would make is that I tend to explictly convert text values to numbers to avoid any potential problems. eg - the mobile players can behave differently and this syntax will be more guaranteed to work everywhere.
Sum(Value(lbl_1.Text) , Value(lbl_2.Text), Value(lbl_3.Text))
The second point is that this will cause a cross screen dependency between screen 2 and screen 1, which is likely to cause a warning in the "app checker". For a small app, this will be ok but on a larger app, it would be better to minimise these types of dependencies by using a variable.
To use a variable, you would locate the formula that you use on screen 1 to navigate to screen 2, and you would pass the calculation in the call to navigate.
Navigate(Screen2,
None,
{locTotal:Sum(Value(lbl_1.Text) , Value(lbl_2.Text), Value(lbl_3.Text))}
)
On label 5, you can then set the text property to locTotal to display the total.