To find the values of k

This topic has expert replies
Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pm
Thanked: 11 times
Followed by:8 members

To find the values of k

by gmattesttaker2 » Mon Dec 23, 2013 10:46 pm
Hello,

Can you please assist with this?

If k/4, k/5 and k are all positive integers and
k less than or equal to 1000 , how many possible different
values does k have?

(A) 65
(B) 60
(C) 55
(D) 50
(E) 45

OA: D

Thanks a lot,
Sri
Source: — Problem Solving |

User avatar
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pm
Thanked: 448 times
Followed by:34 members
GMAT Score:650

by theCodeToGMAT » Mon Dec 23, 2013 10:54 pm
k/4, k/5 and k are INT

K <= 1000

The minimum value of k = 4 * 5 = 20 x _

So, we need to find 20 factors in 1000

==> 1000/20 = 50

{D}
R A H U L

Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pm
Thanked: 11 times
Followed by:8 members

by gmattesttaker2 » Tue Dec 24, 2013 12:12 am
theCodeToGMAT wrote:k/4, k/5 and k are INT

K <= 1000

The minimum value of k = 4 * 5 = 20 x _

So, we need to find 20 factors in 1000

==> 1000/20 = 50

{D}
Hi Rahul,

Thanks for your reply. I was just wondering why we divide 1000 by 20 here?

I was trying to find the values as follows: 20 x 1 = 20, 20 x 2 = 40 ... 20 x 50 = 1000
Hence, we have 50 values.

I just wasn't sure why we have to divide 1000 by 20. Thanks for your help - Sri

User avatar
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pm
Thanked: 448 times
Followed by:34 members
GMAT Score:650

by theCodeToGMAT » Tue Dec 24, 2013 12:20 am
gmattesttaker2 wrote:
theCodeToGMAT wrote:k/4, k/5 and k are INT

K <= 1000

The minimum value of k = 4 * 5 = 20 x _

So, we need to find 20 factors in 1000

==> 1000/20 = 50

{D}
Hi Rahul,

Thanks for your reply. I was just wondering why we divide 1000 by 20 here?

I was trying to find the values as follows: 20 x 1 = 20, 20 x 2 = 40 ... 20 x 50 = 1000
Hence, we have 50 values.

I just wasn't sure why we have to divide 1000 by 20. Thanks for your help - Sri
Hello Sri, it's the same thing..

For example.. if we want to find factors of "2" in between "2" to "10", inclusive.. then we do 10/2 = 5
Other way, the method you used, is:
2x1, 2x2, 2x3, 2x4, 2x5 ...
Both methods are fine, but by dividing we saved time.. ;)
R A H U L

Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pm
Thanked: 11 times
Followed by:8 members

by gmattesttaker2 » Tue Dec 24, 2013 11:08 am
theCodeToGMAT wrote:
gmattesttaker2 wrote:
theCodeToGMAT wrote:k/4, k/5 and k are INT

K <= 1000

The minimum value of k = 4 * 5 = 20 x _

So, we need to find 20 factors in 1000

==> 1000/20 = 50

{D}
Hi Rahul,

Thanks for your reply. I was just wondering why we divide 1000 by 20 here?

I was trying to find the values as follows: 20 x 1 = 20, 20 x 2 = 40 ... 20 x 50 = 1000
Hence, we have 50 values.

I just wasn't sure why we have to divide 1000 by 20. Thanks for your help - Sri
Hello Sri, it's the same thing..

For example.. if we want to find factors of "2" in between "2" to "10", inclusive.. then we do 10/2 = 5
Other way, the method you used, is:
2x1, 2x2, 2x3, 2x4, 2x5 ...
Both methods are fine, but by dividing we saved time.. ;)

Cool. Thanks a lot Rahul. Best Regards - Sri