a, b, c and d is m

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a, b, c and d is m

by sanju09 » Sat Jun 19, 2010 2:13 am
If a < b < c < d and the average (arithmetic mean) of a, b, c and d is m, which of the following is true?

I. a + b < c + d
II. m < d and a < m
III. b < m < c

(A) I only
(B) II only
(C) III only
(D) I and II only
(E) II and III only
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by kvcpk » Sat Jun 19, 2010 2:15 am
sanju09 wrote:If a < b < c < d and the average (arithmetic mean) of a, b, c and d is m, which of the following is true?

I. a + b < c + d
II. m < d and a < m
III. b < m < c

(A) I only
(B) II only
(C) III only
(D) I and II only
(E) II and III only

IMO D

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by amising6 » Sat Jun 19, 2010 2:22 am
sanju09 wrote:If a < b < c < d and the average (arithmetic mean) of a, b, c and d is m, which of the following is true?

I. a + b < c + d
II. m < d and a < m
III. b < m < c

(A) I only
(B) II only
(C) III only
(D) I and II only

(E) II and III only
me solving this would take 4 number satisfying condition i.e a=2,b=3,c=4,d=5 then m=3.5
I. a + b < c + d
true as a+b<c+d a,b are lesthan c as well as d


II. m < d and a < m
sarithmetic mean will will lie betweeen band c
so true
3.5<5
and 2<3.5
true

III. b < m < c


so i guess all of them will be true
Ideation without execution is delusion

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by selango » Sat Jun 19, 2010 2:25 am
Its seems 3 can be true.

the mean will be bw b and c

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by selango » Sat Jun 19, 2010 2:30 am
yes,all options are true.

surely the mean will be bw b and c

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by kvcpk » Sat Jun 19, 2010 2:31 am
selango wrote:Its seems 3 can be true.

the mean will be bw b and c
Try this case: 1<2<100<200

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by sanju09 » Sat Jun 19, 2010 2:39 am
kvcpk wrote:
selango wrote:Its seems 3 can be true.

the mean will be bw b and c
Try this case: 1<2<100<200
Well, the arithmetic mean of 1, 2, 100, and 200 is still between 2 and 100, so what's the hush-hush?
The mind is everything. What you think you become. -Lord Buddha



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by selango » Sat Jun 19, 2010 2:41 am
kvcpk,

here mean is 75.75

2>75.75<100.

3rd equation satisifed here

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by kvcpk » Sat Jun 19, 2010 2:57 am
selango wrote:kvcpk,

here mean is 75.75

2>75.75<100.

3rd equation satisifed here

oops!! wrong example. try this:
1<2<3<3000

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by sanju09 » Sat Jun 19, 2010 2:59 am
kvcpk wrote:
selango wrote:kvcpk,

here mean is 75.75

2>75.75<100.

3rd equation satisifed here

oops!! wrong example. try this:
1<2<3<3000
now is fine
The mind is everything. What you think you become. -Lord Buddha



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