People had to decide whether to make a mock investment with a person or not. They did get to see that person’s track record for returning the money they received.
Older people trust cheaters more often than young people by a fair margin.
Why this is, is still speculated. In questions after it seems the older people were not worried about losing the money. They seemed to think it was more important to be good to the other person and give them a chance.
Citation: Bailey, P., Szczap, P., McLennan, S., Slessor, G., Ruffman, T., & Rendell, P. “Age-related similarities and differences in first impressions of trustworthiness” Cognition and Emotion (2015).