I'm trying to help some people in management understand how long it takes to prepare customize training. Can anyone help me complete this sentence:

For every hour of delivery time, there is ?? hours of design time (for stand up/live training)

I'd appreciate a reference, but I'll take an experienced estimate.

10-40 hours depending on the state of the content. Been doing this for 15 years and hold a PhD in Human Resource Development.

Also google it. I have found stuff for e-learning doing that.

Ben's estimate is good. Thumbrules for development time to classroom training time will vary based on content and information sources. When the scope of development is well known or I just have to slightly modify existing material to meet the client's needs, I've used a 14:1 ratio but have gone as low as 10:1. When the scope of development was not well defined, or there is no source information and the technical content required a higher level of understanding or a high level of detail, I've used 20:1 or higher. I've had clients that use 40:1. You also have to know the capabilities of the developer and their comfort level with the topic. Some developers can bang out training materials quicker than others.