To answer this question you need to interpret the ratio of the money correctly. We only know Dwayne money, so it's better to solve the ratio which was related to Dwayne. In this case, it was Kendra or Tom.
Dwayne money = $5
Kendra money= 1/10 Dwayne money= 1/10 x $5= $0.5
Juan money= 1/10 Kendra money = 1/10 x $0.5= $0.05
Tom money = 10 x Dwayne money = 10 x $5 = $50
Ruth money = 10 x Tom money = 10 x $50= $500
