Well if she is making dinner for 10 people and each person want 2 pieces then you need to multiple 10 x 2 = 20. So she is going to need to make 20 pieces.
If each of her pumpkin pies only has 8 pieces then she is going to have to make 3 pies.
3 pies x 8 pieces = 24 pieces of pumpkin pie. So she has to make 3 pies because she needs 20 pieces since everyone wants 2.
In conclusion Mrs. Owens has to make 3 pies and she is going to have 4 pieces left over.
