The Excel file President's Inn Guest Database provides a list of customers, rooms they occupied, arrival and departure dates, number of occupants, and daily rate for a small bed-and-breakfast inn during one month. Room rates are the same for one or two guests; however, additional guests must pay an additional $20 per person per day for meals. Guests staying for seven days or more receive a 10% discount. Apply IF function to calculate the number of days that each party stayed at the inn and the total revenue for the length of stay.

=SUM (20 * (guests - 1) * days, room cost * rooms*days) * IF (days=>7,0.9,1)

Explanation:

=SUM (20 * (guests - 1) * days, room cost * rooms*days) * IF (days=>7,1-discount, 1)

The first part, we determinaate the additional per mean.

The first person meal is included in the room cost thus, we subtract it from the number of guest that pay it.

Then, we multiply that by $20 each mean and by the days the guests stay.

We also add to the meal cost the room cost, which the room times days.

Then, this will be subject to an IF scenario, if the days are above or equal to 7 we are going to multiply by 0.9 which is 1 less the discount cell amount

if not, then we multiply by 1 as the price remains the same.