Okay first you need to convert 0.2 to a percentage which would be 20% then 20% + 20% = 40% then it says he read 50%, 50% of 36 means that you have to multiply 36 two times to get, 72 then you do 72 * 40% = 28.8 = 29 + 72 = 101 pages in all then 101- 40%= 60.6 is how many pages were read on Monday and Tuesday.
The correct answer is actually (a) because rate of change is x/y (or that's how I learned it) then the more big the slope the bigger the rate of change
