A few of these agents want the first 50 pages sent with the query. I’ve got to admit I’m more worried about getting them hooked at the moment. I can’t tell you how long BR and I’ve worked on the first few pages to make them perfect.
But, the usual partial request is either the first 3 chapters or first 50 pages. And that’s when I went “Well, first three chapters we’ll be good on. But where is Page 50?” As luck would have it, Page 50 is in Chapter Four. We’re working on Chapter Three. That puts us at Page 44.
Page 50 isn’t as far away as I thought it might be. We can easily get through Chapter Four before my targeted date to begin querying again. Perfect! I’m thrilled. Now, back to revising Chapter Four before BR emails demanding to see the pages.
Amanda's Blog 
so do you just send 50 pages even if it ends mid sentence? Mom
No, you just cut off that last sentence. But if it ends mid-paragraph you send only part of the paragraph.