The answer to number 8 would be twelve because.....
if he read 4 pages in 8 minutes he is reading a page in 2 minutes so basically you could multiplt the number of pages he read by 2 and that would give you the answer.
The equation for this would be 41/4 + 52/3 - 41/3= ? So then you just change all the denominators to their lcm, which is 12 and multiply the numerator accordingly. 123/12 + 208/12 - 164/12 = 167/12