The old lady selling eggs explained the process.

The old woman sells eggs, which is interesting and generous. She saw people selling half and giving half a box of eggs. When she saw four people, she sold all the eggs in the box. How many boxes of eggs are there in the box

This is the topic?

The answer should be 15 boxes of eggs.

When I met the last person, I sold half and gave half a box, which was just sold out.

So the last person gets: 0.5X2= 1 (box) eggs.

I met a third person, sold half and gave away half a box.

So: (1+0.5)X2=3 (box)

I met the second person, sold half and gave away half a box.

So: (3+0.5)X2=7 (box)

I met the first person, sold half and gave away half a box.

So: (7+0.5)X2= 15 (box)

So there are 15 boxes of eggs in the box.