1.13 The Connecticut River Bridge is a railroad drawbridge.

The Federal law requires Amtrak to leave it open except when trains are approaching.

Wilson (Proceedings of ICE, 2003) studied the number of bridge operations per month. This area has considerable commercial and navy traffic as well as summer activities. A histogram and dotplot for the number of operations of the Connecticut River Bridge are given in Figure below. Describe the strengths and weaknesses for each of the two types of plots.

2 2 2 2 4 4 5 5 6 5 5 6 7 5 5 7 7 7 7 5 5 8 7 7 7 5 5 5 5 5 5 5 5 5 5 5 5 7 5 7 7 5 5 6 7 7 7 7 7 7 6 5 5 5 7 6 5 7 7 6 5 6 7 6 6 6 6 7 7 5 5 7 5 6 7 6 6 7 6 5 6 7 7 7 7 5 7 6 7 7 6 7 6 7 5 7 6 7 7 7 5 5 7 7 5 7 8 7 7 7 7 6 7 7 7 a Construct a frequency histogram for the numbers of crew members.
b On how many flights were more than five crew members sent into space?
c What percent of flights were manned with at most three personnel?
d If the above data is in chronological order of flights (by row), what kind of long-term pattern do you notice in the number of crew sent into space with the orbiter?

Transcribed Image Text:

Number of months 3 2. 1 0 0 100 200 +1-8 50 150 400 500 600 300 Number of operations 250 250 350 Connecticut bridge operations 450 550