I answered these questions based on:
1. what would be appropriate/beneficial for the tasks I think would be most closely related to the job I'm applying for.
2. prior informal research within the actual department I plan to work at, asking the other employees what they need or have been lacking in terms of human resource.
3. the interviewer's body language; encouraging what they reacted positively to, and keeping information to a minimum when I sensed potential controversy.

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I got the job (applied for a marketing/sales position in a computer hardware store, selling mostly Apple products to college kids). My personal answers to the following:
1. Strengths
(I aimed to tell what good values I have indirectly)
+ personable, excel in interpersonal relationships (good communication skills)
-----------------------> I was then asked how am I personable; I mentioned in my last customer-service-related job as a door-to-door sales distributor, I had to meet with an average of 300 customers on a daily basis; and so I can deal with high-pressure situations as such.
+ very detail-oriented (observant/analytical)
+ don't like/try not to give false promises (reliable/trustworthy/honest)
+ see assigned tasks/promises to the end (dependable, dedicated; ref. above)
+ perfectionist-ic; make sure things are done right (good work ethics)

2. Weakness(es. My interviewer asked only for one)
(I stated it matter-of-fact-ly, just to get it out there and make it seem as if I'm not that affected by it enough to hurt my self-esteem)
- perfectionist-ic; tend to over-analyze sometimes just to get things done right
(then I mentioned I'm working on taking it easy, for the most important thing is the company's and customer's satisfaction, and 'it' is getting better now)


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I hope this helps! It's pretty tricky, especially when it comes to describing your pros and cons realistically and constructively. So long you show motivation, dedication, and effort, I doubt you'll do poorly with these questions.

I think there is definitely more pros then cons with this. You just have to do your homework on this. It will pay off in the long run. Keep up the good work. actos lawsuits