The radius r of a plastic tube used in manufacturing a child’s toy must not differ from the
standard s by more than 3 millimeters. The manufacturing engineers express this as |r – s| 3. If
the standard s is 49, solve the inequality for the radius r. Express the answer in set–builder
notation.
The equation that represents the proper traffic control and emergency vehicle response
availability in a small city is 2P + 3F 23, where P is the number of police cars on active duty and
F is the number of fire trucks that have left the firehouse in response to a call. In order to comply
with staffing limitations, the equation 2P + F 17 is appropriate. The number of police cars on
active duty and the number of fire trucks that have left the firehouse in response to a call cannot
be negative, so P 0 and F 0. Graph the regions satisfying all the availability and staffing
requirements, using the horizontal axis for P and the vertical axis for F. If 5 police cars are on
active duty and 5 fire trucks have left the firehouse in response to a call, are all of the
requirements satisfied?