Round 55 to the nearest tenth and then divide the number by 2

30

Step-by-step explanation:

55 rounded to the nearest ten is 60

60/2=30

30

Step-by-step explanation:

55 is closer to 60 than 40. And you divide 60 by 2 you get  30.

f(x) has value 150 at x= 0

and 0 at x= 3

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