You use this calculated total of 11,582.13 euros as a basis for the rest of your calculation to calculate the percentage of the individual costs in cells B5 to G5.
To calculate percentages, click cell B5 and enter the following formula:
The formula calculates the percentage of the value in cell B4 to the total value in cell B6 for you. Entering the dollar sign when referring to B6 (i.e. $B$6) is essential to being able to copy the formula more effectively in the next step. The dollar signs ensure that Excel copies the formula without changing the reference to the grand total.
As a result, you get the percentage of the costs of the individual rooms in the total.