CF does not change to text to Value.
As I see you trying to SUM one cell only?
You can try like this:
Excel 2010<table rules="all" style=";background-color: #FFFFFF;border: 1px solid;border-collapse: collapse; border-color: #BBB" cellpadding="2.5px"><colgroup><col style="background-color: #DAE7F5" width="25px"><col><col></colgroup><thead><tr style=" background-color: #DAE7F5;text-align: center;color: #161120"><th>
</th><th>A</th><th>B</th></tr></thead><tbody><tr><td style="color: #161120;text-align: center;">1</td><td style="text-align: right;;">8</td><td style="text-align: right;;">
</td></tr><tr><td style="color: #161120;text-align: center;">2</td><td style="text-align: right;;">
</td><td style="text-align: right;;">8</td></tr></tbody></table>
Sheet3
<table rules="all" style=";border: 2px solid black;border-collapse:collapse;padding: 0.4em;background-color: #FFFFFF" cellpadding="2.5px" width="85%"><tbody><tr><td style="padding:6px">
Worksheet Formulas<table rules="all" style="border: 1px solid;text-align:center;background-color: #FFFFFF;border-collapse: collapse; border-color: #BBB" cellpadding="2.5px" width="100%"><thead><tr style=" background-color: #DAE7F5;color: #161120"><th width="10px">Cell</th><th style="text-align:left;padding-left:5px;">Formula</th></tr></thead><tbody><tr><th style=" background-color: #DAE7F5;color: #161120" width="10px">B2</th><td style="text-align:left">=SUM(
VALUE(A1))</td></tr></tbody></table></td></tr></tbody></table>
But this is quite akward way of using SUM for one cell only
You can change that to
Excel 2010<table rules="all" style=";background-color: #FFFFFF;border: 1px solid;border-collapse: collapse; border-color: #BBB" cellpadding="2.5px"><colgroup><col style="background-color: #DAE7F5" width="25px"><col><col></colgroup><thead><tr style=" background-color: #DAE7F5;text-align: center;color: #161120"><th>
</th><th>A</th><th>B</th></tr></thead><tbody><tr><td style="color: #161120;text-align: center;">1</td><td style="text-align: right;;">8</td><td style="text-align: right;;">
</td></tr><tr><td style="color: #161120;text-align: center;">2</td><td style="text-align: right;;">
</td><td style="text-align: right;;">8</td></tr></tbody></table>
Sheet3
<table rules="all" style=";border: 2px solid black;border-collapse:collapse;padding: 0.4em;background-color: #FFFFFF" cellpadding="2.5px" width="85%"><tbody><tr><td style="padding:6px">
Worksheet Formulas<table rules="all" style="border: 1px solid;text-align:center;background-color: #FFFFFF;border-collapse: collapse; border-color: #BBB" cellpadding="2.5px" width="100%"><thead><tr style=" background-color: #DAE7F5;color: #161120"><th width="10px">Cell</th><th style="text-align:left;padding-left:5px;">Formula</th></tr></thead><tbody><tr><th style=" background-color: #DAE7F5;color: #161120" width="10px">B2</th><td style="text-align:left">=VALUE(
A1)</td></tr></tbody></table></td></tr></tbody></table>
Which give the same result