For both brevity and privacy, I may be a bit sparse on the details.

I work for a small business that is small enough that there is no formal, dedicated HR person, let alone department. In the past, the owner handled all HR and payroll related matters, and is only recently beginning to delegate some of this work so that he can more easily tend to "owner of the business" stuff.

Today I was asked to interview potential candidates to fill some open positions (customer service related) we have.

I was specifically asked to do a brief phone interview first, mainly to assess their phone skills. I was not given a list of any specific questions to ask, so on my own I came up with these:

What can you tell me about your past work experience?

What is your availability during the week?

Do you have a (industry specific credential)?

What accomplishment are you the proudest of?

How much experience do you have using computers that run (specific OS)? How are your computer skills in general?

What I am stuck on is what to ask during the second interviews, which he wants conducted in person. (I have not done any of the second interviews yet, but they are scheduled for tomorrow.) When I asked the owner what I should ask, he said he wanted me to ask about their work experience (not realizing I already did during the phone interviews) and how well they can take directions. At that point, a work issue came up and we were never able to finish talking about what else he specifically wants asked.

Now for the actual question:

How do I find out how well a candidate takes direction? If I just ask, the obvious answer is going to be "of course!" and I won't necessarily learn anything about them from that.

Would it be appropriate to provide them paper and pen, and ask them to solve a short math problem?

My theory is if I verbally ask them to please add one thousand two hundred ninety and four thousand five hundred one, then it would directly test this and their listening skills. But if this is not appropriate, or if there is a much better question or test, please tell me! I just have no other idea how to assess someone else's ability to take direction within the context of an interview, and I want to make sure I am doing this the best way possible.