How many different ways can you select a pilot and...

BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

This topic has expert replies

Post new topic Post Reply

Previous Topic Next Topic

swerve: Legendary Member; Posts: 2499; Joined: Sun Oct 29, 2017 2:04 pm; Followed by:6 members

How many different ways can you select a pilot and...

by swerve » Tue Dec 26, 2017 2:57 pm

How many different ways can you select a pilotn and a co pilot if you have 100 people to choose from?

(A) 199
(B) 200
(C) 398
(D) 4950
(E) 9900

The OA is E.

Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks.

Quote

Source: Beat The GMAT — Problem Solving | Tue Dec 26, 2017 2:57 pm

elias.latour.apex: Master | Next Rank: 500 Posts; Posts: 228; Joined: Thu Apr 20, 2017 1:02 am; Location: Global; Thanked: 32 times; Followed by:3 members; GMAT Score:770

by elias.latour.apex » Wed Dec 27, 2017 4:41 am

If you have 100 people to choose from, and you want to select a pilot, then there are 100 different people you can choose.
Once you have selected the pilot, you now have 99 people to choose from for the co-pilot.

Accordingly, there are 99 x 100 = 9900 different combinations of pilot and co-pilot possible.

Elias Latour
Verbal Specialist @ ApexGMAT
blog.apexgmat.com
+1 (646) 736-7622

Quote

GMAT/MBA Expert

Scott@TargetTestPrep: GMAT Instructor; Posts: 8086; Joined: Sat Apr 25, 2015 10:56 am; Location: Los Angeles, CA; Thanked: 43 times; Followed by:29 members

by Scott@TargetTestPrep » Wed Sep 04, 2019 5:21 pm

swerve wrote:How many different ways can you select a pilotn and a co pilot if you have 100 people to choose from?

(A) 199
(B) 200
(C) 398
(D) 4950
(E) 9900

The OA is E.

Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks.

The number of ways to select a pilot of co-pilot is 100P2 = 100 x 99 = 9900.

Answer: E

Scott Woodbury-Stewart
Founder and CEO
[email protected]