Excel 2013 & 365 In Pictures

16 Drag it to cell M4.

The worksheet should look like this:

By employing an absolute reference—using the $ symbol to make each formula use the same cell containing the frog price—the formula stays accurate for all months.

17 In cell B5 in the Revenue sheet, edit the formula...

...to make cell G6 in the Numbers Per-Frog sheet an absolute reference.

18 Use the Fill Handle to copy the formula in cell B5...

...so the Revenue sheet shows each month's net revenue.