data validation

[ravitejt]

Dear Experts

I have done data validation such that A2 + A3 should be equal to A1.
A1 = 100
A2 = 50
A3 = 50.

I want to change A2 to 40 and A3 to 60.

How can I do validation such that it should show error only after entering both values?

 

[portews]

Put the following in the conditional formatting "Use formula...":

=not(A1=A2+A3)

set the format (I usually set the fill color) and apply to the cells you want.