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Do you want the big cup or small cup?

Can I say:

I want to smaller one. (so the small one)
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PreciousJonesCan I say:
I want to smaller one.
No. You can say I want the small one or I want the smaller one.

CJ
Comments  
It sounds odd for you have been asked to choose between the small and the big.

This sounds fine to me:

I want the small.
Students: We have free audio pronunciation exercises.
 CalifJim's reply was promoted to an answer.
Thank you, CaifJim.
CalifJim
PreciousJonesCan I say:I want to smaller one.
No. You can say I want the small one or I want the smaller one.

CJ
sorry that was a typo!
Students: Are you brave enough to let our tutors analyse your pronunciation?
PreciousJonessorry that was a typo!
OK. I wasn't sure. "want to" is also a common combination in English.

CJ