Solution:
Given that,
14 empty water bottles weigh 4.5 pounds
[tex]\text{weight of 1 empty bottle } = \frac{4.5}{14}\\\\\text{weight of 1 empty bottle } = 0.3214\ pounds[/tex]
Weight of 9 empty bottles = 9 x weight of 1 empty bottle
Weight of 9 empty bottles = 9 x 0.3214
Weight of 9 empty bottles = 2.8926
Thus weight of 9 empty water bottles is 2.8926 pounds