<span>y = 10x * sin(x)
y' = 10 * (x * cos(x) + sin(x))
x = pi/2
y' = 10 * ((pi/2) * cos(pi/2) + sin(pi/2)) = 10 * ((pi/2) * 0 + 1) = 10 * 1 = 10
y - 5pi = 10 * (x - (pi/2))
y - 5pi = 10x - 5pi
y = 10x</span>
The first one is A and the second one is B, hope this helps!!
In order to find who has read more pages, let's find the number of pages read by each one.
The number of pages read by Clancey is:

The number of pages read by Ethan is:

So Ethan read more pages.
The combined number of pages in both books is 240 + 170 = 410.
The combined number of pages read is 60 + 68 = 128
So the fraction is:
(20+2.5)x = cost
when x equals number of tickets
(20+2.5)24 = 540