Final answer:
To apply the comma style number format to a cell range in Excel, select the range and choose the 'Comma' format from the 'Format Cells' dialog box.
Step-by-step explanation:
To apply the comma style number format to a cell range in Excel (ex: C4:C15), you can follow these steps:
Select the cell range you want to apply the comma style number format to (in this case, C4:C15).
Right-click and choose 'Format Cells' from the context menu.
In the 'Format Cells' dialog box, go to the 'Number' tab.
Choose 'Number' from the category list.
Select the 'Comma' format from the list of options.
Click 'OK' to apply the comma style number format to the selected cell range.
By applying the comma style number format, any numbers entered into the selected cell range will be displayed with commas separating the thousands, making it easier to read.