Ok she started with 31 she sold 1/2 of the 31 thats 15 and 1/2 + 1/2 = 16
31 - 16 =15
she sold 1/2 of the 15 thats 7 and 1/2 + 1/2 =8
15-8=7
then 1/2 of 7 which is 3 and 1/2 +1/2 = 4
7-4=3
then 1/2 of 3 which is 1 and 1/2 plus 1/2 = 2
3-2=1 egg that she took home to cook!
so customer
1 bought 16 eggs
2 bought 8 eggs
3 bought 4 eggs
4 bought 2 eggs