Answer:
15 weeks
Step-by-step explanation:
They run the add 7 times per 1 day for a week (7 days) which makes $1,800
1800/7=257.14 /7 again for 7 times that day =$36.73
They make $36.73 per one ad.
1800*15=27,00 so it would take 15 weeks to sell the 27,000 tickets