combination or permutation?

[tRNA]

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Jill has 6 different books. In how many ways can jill select 2 different books?
a) 36
b) 30
c) 18
d) 15
e) 12

this question is from an ADA test and the correct answer they give is B, which indicates that it's a permutation problem, so I suppose they just multiplied 6(5)=30......but i think it should be D since I think it should be a combination problem cuz in the question they said " ...can jill SELECT 2..." not "ARRANGE" so the word arrange indicates order and the word select doesn't...am I right??
using the combination formula 6!/(6-2)!2! answer comes out to 15 (D)
I actually asked a tutor and he said it should be D too...at the same time I am sure that ADA could not have missed this one..

 

[Ex_EE]

If it really reads select then 15 is right. Unless you include in different ways to select which one you pick first and then second. In this case then they would be right. It leaves a lot of room for interpretation.

 

[Streetwolf]

An example of a poorly worded problem.

I see what you're saying - that once she has the books in front of her it doesn't matter if she took book 1 then book 2 or if she took book 2 then book 1.

But technically the wording says: how many ways can she select the two books?

She can select book 1 followed by book 2... or she could select book 2 followed by book 1.

The question is just bad.

 

[Law0830]

I agree very poorly written question but if you need help deciphering between combination and permutation is that combination is the formation of a group and permutation is everything else. This does seem to be a permutation because your not putting them into a group formation. Hope that helps.