Nitration of Naphthalene Having Electron Withdrawing Group

In the following nitration which one out of 50 and 51 will be the major product.


[![enter image description here](https://i.stack.imgur.com/ZqGHe.png)](https://i.stack.imgur.com/ZqGHe.png)


In my book it is said that (51) will be major.But in [this video](https://www.youtube.com/watch?v=22-Sou-4Q5o) it is said that (50) will be major.I'm confused.


Oh yes I saw this answer too [Nitration in anthracene and naphthalene](https://chemistry.stackexchange.com/questions/10736/nitration-in-anthracene-and-naphthalene) but did'nt help in my case.


