SUMPRODUCT Blank Cells with LEFT & RIGHT

Welcome to the forum

Please attach a sample workbook (not a picture or pasted copy). Make sure there is just enough data to demonstrate your need. Include a BEFORE sheet and an AFTER sheet in the workbook if needed to show the process you're trying to complete or automate. Make sure your desired results are shown, mock them up manually if necessary.

Remember to desensitize the data.

Click on GO ADVANCED and then scroll down to Manage Attachments to open the upload window.

Try this

=IFERROR(SUMPRODUCT(LEFT(A1:A4,2)+(RIGHT(A1:A4,8))),"")

	A
1	00:00:05:11
2	00:00:01:41
3	00:00:13:43
4
5	00:01:13:32
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100

C1=SUM(IF(ISNUMBER((LEFT(A1:A100,2)+0+(RIGHT(A1:A100,8)+0))),LEFT(A1:A100,2)+0+(RIGHT(A1:A100,8)+0)))

control+shift+enter

Administrative Note:

Welcome to the forum.

We would very much like to help you with your query, however it has been brought to our attention that the same query has been posted on one or more other forums and you have not provided the required cross-post link(s) here. We allow cross posts, but you must give us a link to the post in the other forum.

Please see Forum Rule #3 about cross-posting and adjust accordingly. Read this to understand why we (and other sites like us) consider this to be important.

(Note: this requirement is not optional. No help to be offered until the link is provided.)