Adding WHERE condition in "Calculations" tab of SSAS Cube Designer

Question

I have an existing calculated measure in my SSAS cube [Total Hours]. The expression for this is:

([Measures].[working Hours] + [Measures].[working minutes]/60)

I have to create a new Measure by adding a where condition to the above calculated measure like: [Measures].[Status Flag] = 'YES'

How can I add a where condition to an existing calculated measure?

I tried to use the existing Measure like this and create the new one. Is this right?

[Measures].[Total Hours] & ([Measures].[Status Flag] = 'YES')