Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2512:30 AM EDT
-01:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
Apr 2601:30 AM EDT
-02:30 AM EDT
Learn how Keshav, a Chartered Accountant, scored an impressive 705 on GMAT in just 30 days with GMATWhiz's expert guidance. In this video, he shares preparation tips and strategies that worked for him, including the mock, time management, and more.
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
May 0111:00 AM PDT
-12:00 PM PDT
Free- full-length test + 15 concept videos + 150+ short videos + study plan!
28 Aug 2011, 17:53
Kudos
Bookmarks
Hi Guys,
Small question. When we have multiple combinations or permutations within the same problem, do we add or multiply the individual comb./perm. to get the total number of possibilities ?
Thanks in advance for your help
Small question. When we have multiple combinations or permutations within the same problem, do we add or multiply the individual comb./perm. to get the total number of possibilities ?
Thanks in advance for your help
Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
29 Aug 2011, 00:39
Kudos
Bookmarks
jinkev
If the relation ship between these two different combination is OR than its ADD
Ex. A die is thrown 2 times, how many combinations are possible that sum of the outcomes of two throws is either 6 OR 7
If the relation ship between these two different combination is AND than its MULTIPLE
Ex. Two dice are thrown 2 times, how many combinations are possible that sum of the outcomes of two throws in each dice is 6 AND 7 respectively
31 Aug 2011, 22:32
Kudos
Bookmarks
jinkev
As mentioned above, it depends on whether it is an 'OR' relation or an 'AND' relation.
OR relation
I have chosen a red shirt to wear. I have 3 pairs of trousers and 2 pairs of jeans. In how many ways can I choose my dress?
I need to choose either a pair of trousers OR a pair of jeans. This is an OR relation. We need to add here. Total number of ways = 3+2 = 5
AND relation
I have 4 shirts and 3 pairs of trousers. In how many ways can I choose my dress?
I need to choose 1 shirt AND 1 pair of trousers. This is an AND relation. We need to multiply here. Total number of ways = 4*3 = 12
For every one shirt, you have 3 trousers to choose from so a total of 12 combinations.
Take another example: I have 4 shirts, 3 pairs of trousers and 2 pairs of jeans. In how many ways can I choose my dress?
I have to select 1 shirt AND a pair of trousers OR a pair of jeans.
Total combinations = 4 *(3 + 2) = 20
Similarly, you have 10 boys and 20 girls. In how many ways can you select 2 boys and 2 girls?
You have to select 2 boys AND 2 girls. Multiply.
In 10C2 * 20C2 ways
You have 10 boys and 20 girls. In how many ways can you select 4 people such that they have the same gender?
You can select either 4 boys OR 4 girls. Add.
This can be done in 10C4 + 20C4 ways
