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

Redeem

Please provide explanation for these GMAT PREP Questions

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 15
Joined: Sat Aug 08, 2009 7:07 am
Location: PUNJAB
GMAT Score:610

Please provide explanation for these GMAT PREP Questions

by DREAM GMAT » Mon Oct 12, 2009 10:57 am
1. A company assigns ID number to employees. Each is to consist of 4 different digits from 0 to 9 inclusive except 1st digit cannot be 0. How many different combinations are there?
a. 3024
b. 4536
c. 5040
d. 9000
e. 10000


2. Angela's grade was in the 90th percentile out of 80 grades in her class. In another class there were 19 grades higher than Angela's. If nobody had Angela's grade, then Angela was what percentile of the two classes combined?
a. 72
b. 80
c. 81
d. 85
e. 92

Regards
MANDEEP
Top
Source: — Problem Solving |
Senior | Next Rank: 100 Posts
Posts: 80
Joined: Wed Jun 04, 2008 1:16 pm
Thanked: 3 times

Re: Please provide explanation for these GMAT PREP Questions

by mpaudena » Mon Oct 12, 2009 6:14 pm
DREAM GMAT wrote:2. Angela's grade was in the 90th percentile out of 80 grades in her class. In another class there were 19 grades higher than Angela's. If nobody had Angela's grade, then Angela was what percentile of the two classes combined?
a. 72
b. 80
c. 81
d. 85
e. 92

Regards
I've seen question number 2 before. Are you sure that in the second class there aren't 100 grades? That is are you sure you transcribed the question correctly?

If you were accurate then I don't understand the answer and when I did this I just assumed there was 100 grades. I'm sure with that you can find the answer by adding the total number of grades, which is 180 and the totals of Angela's position (72 and 81) which is 153. The resulting percentage is 85.
Top
Legendary Member
Posts: 882
Joined: Fri Feb 20, 2009 2:57 pm
Thanked: 15 times
Followed by:1 members
GMAT Score:690

by crackgmat007 » Mon Oct 12, 2009 8:11 pm
1. B

4 digits

thousands - we have 9 numbers (excluding 0)
hundreds - we have 9 numbers (now incliding 0 & excluding the number assigned for thousands)
tens - 8 numbers
units 7

HTH
Top
User avatar
Community Manager
Posts: 1537
Joined: Mon Aug 10, 2009 6:10 pm
Thanked: 653 times
Followed by:252 members

by papgust » Mon Oct 12, 2009 10:27 pm
Forgive if my question sounds stupid.

For qn #1, it mentions "find different combinations". Do we have to employ permutation formula/ combination formula?

I understand that by using permutation formula, correct answer choice will be 4536 which is part of answer choice. But the word "combinations" confuses me.

Pls help me understand.
Top
Junior | Next Rank: 30 Posts
Posts: 15
Joined: Sat Aug 08, 2009 7:07 am
Location: PUNJAB
GMAT Score:610

by DREAM GMAT » Tue Oct 13, 2009 12:16 am
crackgmat007 wrote:1. B

4 digits

thousands - we have 9 numbers (excluding 0)
hundreds - we have 9 numbers (now incliding 0 & excluding the number assigned for thousands)
tens - 8 numbers
units 7

HTH

thanks

I missed the term "different" n got confused.

Thanks for the Clariifcation.
MANDEEP
Top
Junior | Next Rank: 30 Posts
Posts: 15
Joined: Sat Aug 08, 2009 7:07 am
Location: PUNJAB
GMAT Score:610

Re: Please provide explanation for these GMAT PREP Questions

by DREAM GMAT » Tue Oct 13, 2009 12:25 am
mpaudena wrote:
DREAM GMAT wrote:2. Angela's grade was in the 90th percentile out of 80 grades in her class. In another class there were 19 grades higher than Angela's. If nobody had Angela's grade, then Angela was what percentile of the two classes combined?
a. 72
b. 80
c. 81
d. 85
e. 92

Regards
I've seen question number 2 before. Are you sure that in the second class there aren't 100 grades? That is are you sure you transcribed the question correctly?

If you were accurate then I don't understand the answer and when I did this I just assumed there was 100 grades. I'm sure with that you can find the answer by adding the total number of grades, which is 180 and the totals of Angela's position (72 and 81) which is 153. The resulting percentage is 85.
Your answer is correct but i am not convinced with explanation.

Since statement states that Angela Grade is 90% tile of 80 Grade which mean she has a grade of 72.

Also statement states that another class is having highest grade which is 19 more than Angela's grade i.e. highest grade for other class will (72+19=91).

Now if we take both classes together we have a maximum grade of 91 & Angela scored 72. Now if we calculate the percentile it should be = (72/91)*100 (i.e. 79.*** %tile)

Which is not the available option.

Please clarify if i missed something.

Regards
Mandeep
Top
Post new topic Post Reply
• Page 1 of 1