Show us the equation you have for calculating flow over a horizontal weir...
there is no way we can help you isolate the "X" in "X^1.5" unless we know
the rest of the equation.

Rick


"Shawn" wrote in message
...
I have a formula for finding the flow over a horizontal weir. ( gpm = 3 *
weir L ins. * overflow ins. 1.5th) I want to set up an Excel formula to
give
the result as the overflow inches. ("X" in "X^1.5") How do I do that?