Viper83 wrote:To furnish a room in a model home, an interior decorator is to select 2 chairs and 2 tables from a collection of chairs and tables in a warehouse that are all different from each other. If there are 5 chairs in the warehouse and if 150 different combinations are possible, how many tables are at the warehouse?
a. 6
b. 8
c. 10
d. 15
e. 30
a
150 = (total possible chair combinations) * (total possible table combinations)
Thus, number of table combinations = 150/(total possible chair combinations)
Total possible chair combinations = number of ways to choose 2 chairs from 5 choices = 5C2 = 10.
Number of table combinations = Total combinations/Chair combinations = 150/10 = 15.
Now we can plug in the answer choices, which represent the number of tables, to see which yields 15 possible combinations.
Only answer choice A works:
6C2 = 15.
The correct answer is
A.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at
[email protected].
Student Review #1
Student Review #2
Student Review #3
