At a large university, in the never-ending quest for
a satisfactory textbook, the Statistics Department
has tried a different text during each of the last
three quarters. During the fall quarter, 500 stu-
dents used the text by Professor Mean; during
the winter quarter, 300 students used the text by
Professor Median; and during the spring quarter,
200 students used the text by Professor Mode.
A survey at the end of each quarter showed that
200 students were satisfied with Mean's book, 150
were satisfied with Median's book, and 160 were
satisfied with Mode's book. If a student who took
statistics during one of these quarters is selected at
random and admits to having been satisfied with
the text, is the student most likely to have used the
book by Mean, Median, or Mode? Who is the least
likely author? [Hint: Draw a tree-diagram or use
Bayes' theorem.]
At a large university, in the never-ending quest for
a satisfactory textbook, the Statistics Department
has tried a different text during each of the last
three quarters. During the fall quarter, 500 stu-
dents used the text by Professor Mean; during the winter quarter, 300 students used the text by Professor Median; and during the spring quarter. 200 students used the text by Professor Mode
A survey at the end of each quarter showed that 200 students were satisfied with Mean's book, 150
were satisfied with Median's book, and 160 were
satisfied with Mode's book. If a student who took
statistics during one of these quarters is selected at
random and admits to having been satisfied with
the text, is the student most likely to have used the
book by Mean, Median, or Mode? Who is the least likely author? [Hint: Draw a tree-diagram or use Bayes' theorem.]