Using proportions, it is found that the complete sentence is:
"So I helped 54 customers in 7.5 hours yesterday."
The rule of three is:
0.5 hours - 3.6 customers
7.5 hours - x customers
Applying cross multiplication:
[tex]0.5x = 7.5(3.6)[/tex]
[tex]x = \frac{7.5(3.6)}{0.5}[/tex]
[tex]x = 54[/tex]
54 customers were helped.
A similar problem is given at https://brainly.com/question/24372153