GRE Prep 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.
The number of four-digit numbers
[#permalink]
05 Jan 2022, 06:12
05 Jan 2022, 06:12
Expert Reply
1
Bookmarks
00:00
Question Stats:
61% (00:53) correct
38% (00:56) wrong based on 13 sessions
Hide Show timer Statistics
Quantity A |
Quantity B |
The number of four-digit numbers with distinct digits |
The number of three digit numbers |
A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
Kudos for the right answer and explanation
See more on Numbers Comprehension
Re: The number of four-digit numbers
[#permalink]
10 Jan 2022, 03:34
10 Jan 2022, 03:34
1
The number of four-digit numbers with "distinct" digits -
Since 0 can't be used at thousand's place (that would make it a 3 digit number), we have 9 digits available for it (1 to 9). For hundred's place, 9 digits are available because 0 is now allowed. For ten's and units place 8 and 7 digits are available respectively. So value A is 9*9*8*7 = 4536.
The number of three digit numbers -
Three-digit numbers go from 100 to 999 so value B is 999-100+1 = 900.
Clearly, A is greater than B.
Since 0 can't be used at thousand's place (that would make it a 3 digit number), we have 9 digits available for it (1 to 9). For hundred's place, 9 digits are available because 0 is now allowed. For ten's and units place 8 and 7 digits are available respectively. So value A is 9*9*8*7 = 4536.
The number of three digit numbers -
Three-digit numbers go from 100 to 999 so value B is 999-100+1 = 900.
Clearly, A is greater than B.
gmatclubot
Re: The number of four-digit numbers [#permalink]
10 Jan 2022, 03:34
Moderators:
