Answer :
Let x equals to the time can chris unload the ship’s cargo
2x equals to the time can julissa unload the ship’s cargo
The can be solve by establishing an equation that they can do the job in 6 hours
(1/x) + (1/2x) =1/ 6
X = 9 hrs can chris do the job alone
2x = 18 hrs can julissa do the job alone