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by theCEO » Tue Jun 30, 2015 1:04 am
nahid078 wrote:There are 20 players in a team. How many ways we can select a captain and co-captain from the team?
If we select the captain first: we can choose from 20 players
If we select the cocaptain second: we can choose from 19 players
Therefore the total ways = 20 x 19
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by Brent@GMATPrepNow » Tue Jun 30, 2015 5:59 am
nahid078 wrote:There are 20 players in a team. How many ways we can select a captain and co-captain from the team?
Take the task of selecting players and break it into stages.

Stage 1: Select the captain
There are 20 players to choose from, so we can complete stage 1 in 20 ways

Stage 2: Select the co-captain
There are now 19 players remaining (to choose from), so we can complete this stage in 19 ways.

By the Fundamental Counting Principle (FCP), we can complete the two stages (and thus complete the task) in (20)(19) ways ([spoiler]= 380 ways[/spoiler])

--------------------------

Note: the FCP can be used to solve the MAJORITY of counting questions on the GMAT. For more information about the FCP, watch our free video: https://www.gmatprepnow.com/module/gmat-counting?id=775

Then you can try solving the following questions:

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MEDIUM
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DIFFICULT
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Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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