Can I just report 2 mortgages when I have 3 mortgages for maximize the deduction?

I have 3 mortgages, 2 of them are applied before 2017, the third one was closed on Sep 2018.

The first two mortgages have about 580k balance, and the interest in 2018 is about 23k. 

The third one balance is 510k and the interest is about 2.7k since this one is starting payment from Sep 2018.

Can I just report the two mortgages that applied before 2017? Then I will have 23k deduction for this year.

If add the third one, the total balance will exceed the 750k limit, then I only can apply about 18k deduction for this year.