Here we are given that the Cruise control function on Georgina's car should keep the speed of the car within 3 miles per hour of the set speed.
The set speed is 55 miles per hour.
Upper limit for speed of the car is given by:
55+3 = 58 miles per hour
So upper limit for speed of car is 58 miles per hour.
Lower limit for speed of the car is given by:
55-3 = 52 miles per hour
Lower limit for speed of the car is 52 miles per hour.
So the speed limit for the car would be 52 miles per hour to 58 miles per hour.
Now we can represent it on the number line as shown in attachment.