The number of shoppers queuing at any given time in a certain supermarket in downtown Washington DC can be
approximately represented by the equation:
y = x3 – 14×2 + 50x over the range 0 ≤ x ≤ 8.5, where y is the number queuing and x is the time in hours
after the store opens at 9.00a.m. (So that, for example 10.30a.m. is x=1.5, and 5.30p.m. – when the store
closes is x= 8.5).
Required:
i) The management wants to know when they should deploy more cashiers and the number queuing at
that time.
ii) Determine the number of man-hours spent per day by shoppers queuing.