Subtracting Times & getting a negative answer

[excel on the run]

I need to subtract the "Actual Time,A4" from the "Time Remaining,C3" and if the "Actual Time,A4" is greater than
the "Planned Time,B4" I need to add that difference back on to the "Remaining Time,C3"
In the case below the answer would be "Time Remaining, C4" 3:15

Hope u can help, Thanking You ALL in advance

	A	B	C	D
1	Hours:Minutes 00:00
2	Actual Time	Planned Time	Time Remaining
3			3:35
4	0:50	0:35
5

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EOTR,

 

[shg]

=c3 - a4 + b4

 

[excel on the run]

Only if A4 is greater than B4. Then it should just be C3 - B4

 

[shg]

=c3 - (a4 > b4) * a4 + b4