Alice has read 150 pages, you would multiple 200 by .75 (75%). If Nina had read 50% of her book and she read 150, you multiple by 2, and get 300. So Nina has 300 pages in her book.
These quantities are related linearly with slope
3/2. without knowing the answer choices I can only give you examples of equations that fit
y-2=3/2(x-2). or y=3/2(x) -1
etc
Yes, he is correct, using the distributive property you get the same answer