This section is from the book "Text-Book On Domestic Art", by Carrie Crane Ingalls. Also available from Amazon: Textbook On Domestic Art: With Illustrations And Drafts.
1/6 of half the waist measurement or 1/12 of the whole.
1/4 of half the waist measurement, or 1/8 of the whole.
7/12 of half the waist measurement, or 7/24 of the whole.
Divide the side gores in half for each one.