It varies from to girl to girl. If i really like a girl, i will pursue to get her outside until i do. Sometimes girls ask me to hang out, even if i was already planning on asking her in the future.
It also depends on how often i see her at her workplace. If i see a girl once every 2 months, then it'll take about 4 visits to get her outside. Especially if you have to ask her to hang out, then she needs to be comfortable with you.
Back then when i was visiting places a couple of times per week, i would meet a girl first time at her job say on a sunday, then 2 weekends after that we're hanging out, or the very next time she has off (red vacation lol).