Answer: it has 900,000 more aliens than planet Zamba.
Step-by-step explanation:
Planet Ruba has 1,000,000 aliens.
Planet Zamba has 100,000 aliens.
first, the difference is:
1,000,000 - 100,000 = 900,000
this means that planet Ruba has 900,000 more aliens that planet Zamba.
and the relation comes from:
population of Ruba/population of Zamba
1,000,000/100,000 = 10
this means that planet Ruba has 10 times the amount of aliens that planet Zamba has.