Helga works for a newspaper company. She can write 5 articles every 30 minutes, and she usually works 4 hours a day 5 days a week. If Helga worked an extra 2 hours last Thursday, and an extra 3 hours last Friday, how many articles was she able to write this week? Let's think first. Chain of thought:
Helga writes 5 x 2 = 10 articles per hour. And she can write 10 x 4 = 40 articles every 4 hours. So, the total number of articles she usually writes for a week is 40 x 5 = 200 articles. She was able to write 10 x 2 = 20 articles on her extra 2 hours last Thursday. And she was able to write 10 x 3 = 30 articles on her extra hour last Friday. So, the total number of articles she was able to write on her extra hours is 20 + 30 = 50. Therefore, she was able to write a total of 200 + 50 = 250 this week.
Therefore, the answer is 250.