AD General Fees ... How to understand

[c.b.glover]

Please can some kind soul help me ... I just cannot understand the ad general fee calculations.

I sell at 5.99 and receive 5.52 after BPF

postage is 0.87

ad general fee is 0.79

Order earning is 3.86

The ad fee general was at 10% ! How does this calculate ? can anyone help????

[papso22]

It's 10% of the item plus postage.