10.12 Traffic sign maintenance. Refer to the Journal of Transportation Engineering (June 2013) study of traffic alul NCDOT sign maintenance, Exercise 8.54 (p. 465). Recall that civil engineers...

Extracted text: 10.12 Traffic sign maintenance. Refer to the Journal of Transportation Engineering (June 2013) study of traffic alul NCDOT sign maintenance, Exercise 8.54 (p. 465). Recall that civil engineers estimated the proportion of traffic signs main- tained by the North Carolina Department of Transportation (NCDOT) that fail minimum retroreflectivity requirements. The researchers were also interested in the proportions of NCDOT signs with background colors white (regulatory signs), yellow (warning/caution), red (stop/yield/wrong way), and green (guide/information). In a random sample of 1,000 road signs maintained by the NCDOT, 373 were white, 447 were yellow, 88 were green, and 92 were red. Suppose that NCDOT stores new signs in a warehouse for use as replacement signs; of these, 35% are white, 45% are yellow, 10% are green, and 10% are red. Does the distribution of background colors for all road signs maintained by NCDOT match the color distribution of signs in the warehouse? Test using a