ipad numbers sum of highlighted cells

I recently bought an Ipad and started using numbers. I looked through the questions and answers, but I still couldn't figure this out.

I would like to get a sum of selected cells.

For example, I would selected A1, A3, A5. Nothing happens.

In Excel, there would be sum, average, count, and etc. of the selected cells.

Is there any way I can get a quick look at the sum of selected cells?

Thank you