4. Julissa can unload a ship's cargo twice as fast as Chris. Together, they can unload the cargo in 6 hours. How long would it take each of them working alone to unload the cargo?

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