Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 20 Aug 2014, 14:47

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Exponents on steroids...

Author Message
TAGS:
Current Student
Joined: 28 Dec 2004
Posts: 3405
Location: New York City
Schools: Wharton'11 HBS'12
Followers: 13

Kudos [?]: 158 [0], given: 2

Exponents on steroids... [#permalink]  06 Sep 2005, 10:36
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
If (a+b)^x=a^x + y(a^(x-1)*b^(x-4)) + z(a^(x-2)*b^(x-3)) + z(a^(x-3)*^(x-2)) + y(a^(x-4)*b^(x-1)) + b^x, what is the value of yz?

(A) 24
(B) 30
(C) 36
(D) 42
(E) 50

Intern
Joined: 04 Sep 2005
Posts: 4
Followers: 0

Kudos [?]: 0 [0], given: 0

The factors y & z follow the below shown triangle of values (can't remember its name):

1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1

For the equation given, y=5 & z =10...answer is 50
Current Student
Joined: 28 Dec 2004
Posts: 3405
Location: New York City
Schools: Wharton'11 HBS'12
Followers: 13

Kudos [?]: 158 [0], given: 2

hmm could you shed some light on this?

I figured out what y is, but had hard time figuring z....

basically I know that x =5, then I know that the coefficient of y will also be 5....figuring out z is the hard part...

zag1979 wrote:
The factors y & z follow the below shown triangle of values (can't remember its name):

1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1

For the equation given, y=5 & z =10...answer is 50
Current Student
Joined: 28 Dec 2004
Posts: 3405
Location: New York City
Schools: Wharton'11 HBS'12
Followers: 13

Kudos [?]: 158 [0], given: 2

actually this is a nice chart to remember whenever you have (a+b)^x...

depending on x..you can build out this chart...nice indeed....

can someone show how we can expand the pascal plot...to more than 6...
Manager
Joined: 06 Aug 2005
Posts: 198
Followers: 3

Kudos [?]: 5 [0], given: 0

Just add the two numbers above each number when in the normal isosceles triangle design.

Or use the nCr formula.

Try looking up Pascal's triangle on a search engine on the internet.
Senior Manager
Joined: 15 Aug 2005
Posts: 257
Location: Las Vegas, NV
Followers: 2

Kudos [?]: 0 [0], given: 0

zag1979 wrote:
The factors y & z follow the below shown triangle of values (can't remember its name):

1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1

For the equation given, y=5 & z =10...answer is 50

Zag! Pretty d@mn good! I totally forgot that from high school. That makes these kind of problems a piece of cake.
Similar topics Replies Last post
Similar
Topics:
CR on Steroids 2 07 Jun 2012, 00:52
Exponents 18 08 May 2006, 13:01
exponents 3 05 Nov 2005, 13:19
Exponents 4 28 Sep 2005, 03:31
exponent 1 11 Jan 2005, 19:30
Display posts from previous: Sort by

# Exponents on steroids...

 Powered by phpBB © phpBB Group and phpBB SEO Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.