The traffic flow rate cars per hour across an intersection i
     The traffic flow rate (cars per hour) across an intersection is r(t) = 300 + 1000t - 270t^2, where t is in hours, and t = 0 is 6am. How many cars pass through the intersection between 6 am and 8 am?  Preview cars 
  
  Solution
we are given
traffice flow rate
r(t)=300+1000t-270t^2
t=0 at 6am
now, we can find rate between 6m and 8m
t=8-6
t=2
now, we can plug t=2 and find rate
r(2)=300+1000*2-270(2)^2
r(2)=1220
r(2) =1220 car /hour between 6am to 8am
now, we can find total car by multiplying 2
because total 2 hours between 6am and 8am
so, total car = 1220*2
C=2440 cars..........Answer

