An instructor gives an exam with fifteen questions. Students are allowed to choose any eleven to answer. (a) How many different choices of eleven questions are there?   (b) Suppose six questions require proof and nine do not. (i) How many groups of eleven questions contain four that require proof and seven that do not?   (ii) How many groups of eleven questions contain at least one that requires proof?   (iii) How many groups of eleven questions contain at most three that require proof?   (c) Suppose the exam instructions specify that at most one of the questions 1 and 2 may be included among the eleven. How many different choices of eleven questions are there?   (d) Suppose the exam instructions specify that either both questions 1 and 2 are to be included among the eleven or neither is to be included. How many different choices of eleven questions are there?

Algebra and Trigonometry (MindTap Course List)
4th Edition
ISBN:9781305071742
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:James Stewart, Lothar Redlin, Saleem Watson
Chapter14: Counting And Probability
Section14.1: Counting
Problem 58E: Room Assignments When seven students take a trip, they find a hotel with three rooms available: a...
icon
Related questions
Topic Video
Question
An instructor gives an exam with fifteen questions. Students are allowed to choose any eleven to answer.
(a)
How many different choices of eleven questions are there?
 
(b)
Suppose six questions require proof and nine do not.
(i)
How many groups of eleven questions contain four that require proof and seven that do not?
 
(ii)
How many groups of eleven questions contain at least one that requires proof?
 
(iii)
How many groups of eleven questions contain at most three that require proof?
 
(c)
Suppose the exam instructions specify that at most one of the questions 1 and 2 may be included among the eleven. How many different choices of eleven questions are there?
 
(d)
Suppose the exam instructions specify that either both questions 1 and 2 are to be included among the eleven or neither is to be included. How many different choices of eleven questions are there?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Permutation and Combination
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, probability and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Algebra and Trigonometry (MindTap Course List)
Algebra and Trigonometry (MindTap Course List)
Algebra
ISBN:
9781305071742
Author:
James Stewart, Lothar Redlin, Saleem Watson
Publisher:
Cengage Learning
College Algebra
College Algebra
Algebra
ISBN:
9781337282291
Author:
Ron Larson
Publisher:
Cengage Learning
Holt Mcdougal Larson Pre-algebra: Student Edition…
Holt Mcdougal Larson Pre-algebra: Student Edition…
Algebra
ISBN:
9780547587776
Author:
HOLT MCDOUGAL
Publisher:
HOLT MCDOUGAL
College Algebra (MindTap Course List)
College Algebra (MindTap Course List)
Algebra
ISBN:
9781305652231
Author:
R. David Gustafson, Jeff Hughes
Publisher:
Cengage Learning
Algebra: Structure And Method, Book 1
Algebra: Structure And Method, Book 1
Algebra
ISBN:
9780395977224
Author:
Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
Publisher:
McDougal Littell