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
Please provide explanation for these GMAT PREP Questions
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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?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
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.
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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
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
- papgust
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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.
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.
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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
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Your answer is correct but i am not convinced with explanation.mpaudena wrote: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?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
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.
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