series of numbers

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series of numbers

by LalaB » Sun Jan 01, 2012 2:36 am
in a series of even consecutive numbers, 30 is the eleventh smallest number and 28 is the thirteenth largest number. what is the range of the series?

a)12
b)22
C)30
d)42
e)54
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by rijul007 » Sun Jan 01, 2012 2:44 am
Lets say the series is a,b,c .... , 28, 30, 32, ....

30 is 11th smallest
this implies that 28 is 10th smallest

28 is thirteenth largest


-----(9 nos)---- 28 ----(12 nos)--

range = 9 + 1 + 12 = 22

Option B

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by LalaB » Sun Jan 01, 2012 2:47 am
rijul007 wrote:Lets say the series is a,b,c .... , 28, 30, 32, ....

30 is 11th smallest
this implies that 28 is 10th smallest

28 is thirteenth largest


-----(9 nos)---- 28 ----(12 nos)--

range = 9 + 1 + 12 = 22

Option B
u r on a right way, but made a small mistake in ur thinking. please have one more try

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by rijul007 » Sun Jan 01, 2012 4:04 am
LalaB wrote:
rijul007 wrote:Lets say the series is a,b,c .... , 28, 30, 32, ....

30 is 11th smallest
this implies that 28 is 10th smallest

28 is thirteenth largest


-----(9 nos)---- 28 ----(12 nos)--

range = 9 + 1 + 12 = 22

Option B
u r on a right way, but made a small mistake in ur thinking. please have one more try
Hey,
I still dont see where I am going wrong.
What's the OA?

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by Bharath Krishnan » Sun Jan 01, 2012 5:21 am
Hi,

I am getting the answer D- 42

28 is the 13th largest, that makes the last number to be 52

If 30 is the 11th smallest, then 10 is the first number.

Range: 52-10 = 42.

Answer is D

Please give the OA and correct me if I am wrong.

Bharath-

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by LalaB » Sun Jan 01, 2012 7:00 am
rijul007 wrote:Lets say the series is a,b,c .... , 28, 30, 32, ....

30 is 11th smallest
this implies that 28 is 10th smallest

28 is thirteenth largest


-----(9 nos)---- 28 ----(12 nos)--

range = 9 + 1 + 12 = 22

Option B
please do not forget, that the range is not the difference of terms, but the difference of numbers

according to ur solution, if we have the series 2 4 6 8 , and 6 is the 3d smallest number and the 2nd largest number, then - 2+1+1=4, but the range is 8-2=6


@Bharath Krishnan, yep, the correct answ is D :)

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by rijul007 » Sun Jan 01, 2012 8:04 am
LalaB wrote:
rijul007 wrote:Lets say the series is a,b,c .... , 28, 30, 32, ....

30 is 11th smallest
this implies that 28 is 10th smallest

28 is thirteenth largest


-----(9 nos)---- 28 ----(12 nos)--

range = 9 + 1 + 12 = 22

Option B
please do not forget, that the range is not the difference of terms, but the difference of numbers

according to ur solution, if we have the series 2 4 6 8 , and 6 is the 3d smallest number and the 2nd largest number, then - 2+1+1=4, but the range is 8-2=6


@Bharath Krishnan, yep, the correct answ is D :)
oh yeah.. thanks for pointing out :D