Home > CALC > Chapter 2 > Lesson 2.3.2 > Problem2-116

2-116.

A local fast-food restaurant records data on the rate customers enter their establishment during a typical lunch hour. Using this data in the table below, predict the total number of customers served during this $30$-minute period.

 Time (min) Rate (cust/min) $0$ $4$ $9$ $15$ $19$ $26$ $30$ $12$ $13$ $17$ $23$ $19$ $14$ $6$

A table gives us only select values of a function. We do not know if it is a continuous function.

Though the graph of this rate function was not provided, it is still possible to compute the area under the curve.

Imagine the graph. Now imagine connecting the points with trapezoids or rectangle.

Notice that the $Δx$ is not consistent, so do not use a shortcut (such as the Trapezoidal rule, or sigma notation).