Chuck can ride the merry-go-round 5 times longer than Dave who can only ride it for 10 minutes before getting sick. Erica can stay on the merry-go-round 30% longer than Chuck before getting sick. How long can Erica stay on the merry-go-round? Let's think first. Chain of thought:
Dave can ride the merry - go - round for 10 minutes and Chuck can ride 5 times longer than Dave so he can ride for 10 * 5 = 50 minutes. Erica can stay on 30% longer than Chuck who can ride for 50 minutes so that's an extra .30 * 50 = 15 minutes. Chuck can ride for 50 minutes and Erica can ride an extra 15 minutes for a total of 50 + 15 = 65 minutes.
Therefore, the answer is 65.