# Formula challenge - 2D lookup and sum

### The problem

The data below shows cups of coffee sold at a small kiosk for a week at different hours of the day. The times in column B are valid Excel times.

### The challenge

What formula in cell I5 will correctly sum the total cups sold after 12:00 PM on Tuesday and Thursday? Relevant cells are shaded in green.

For your convenience, the following named ranges are available:

data = C5:G14

times = B5:B14

days = C4:G4

Download the Excel workbook, and leave your answer as a comment below.

### Constraints

- Your formula should dynamically locate the cells to sum, without hardcoded references. In other words, =SUM(D10:D14,F10:F14) is
*not*valid. - Use named ranges when possible to make your formula easy to read.