Estimate the average velocity vave of the car during the first 18 seconds. use the midpoint rule with n = 3. (round your answer to the nearest whole number.)

v_ave=1/12int (t=0 to t=12) v(t) dt
Using midpoint rule with n=3, we shall have:
12/3(v(2)+v(6)+v(10))
=4(20+50+66)
=544 km-s/h
hence:
v_ave=(544 km-s/h)/(12 sec)
=45 km/h (to the nearest whole number)