13 identically sized pieces of timber are x
cm long when put together. How long is each individual piece?

x/13 = y.

Step-by-step explanation: Let x represent the total length of the timber. Then, 13 will represent the number of pieces it will be divided into. Finally, y represents the length of each individual size.

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50

25% is the answer