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Re M26-24 [#permalink]
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 16 Sep 2014, 01:25
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Re: M26-24 [#permalink]
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27 Nov 2014, 16:02
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Average of largest 5 = -185/5 =-37
So the largest numbers are -41, -39, -37, -35, -33
Now if we consider smallest 5, we have to eliminate last 2 numbers, which are -35 and -33
Notice here that the numbers are equally spaced.
So the average of smallest number will just shift 2 place to the left.
Avg= -41
Therefore, total = -41*5= -205
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Re: M26-24 [#permalink]
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04 Feb 2015, 00:55
Can you please explain this step of the solution:
(5x+20)+20=-185
I'm having a difficult time understanding how this 20 appears
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Re: M26-24 [#permalink]
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04 Feb 2015, 01:13
wpereira3 wrote: Can you please explain this step of the solution:
(5x+20)+20=-185
I'm having a difficult time understanding how this 20 appears From previous step - (5x+20)+20=-185 is the same as (5x+40)=-185
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Dear Buenel,
You have mentioned in the solution that
5x+20 is the "sum of five smallest" but isn't it the "Sum of five Largest" because we are dealing with negative numbers (i.e. X is negative)
If this is the case then the answer would be -175.
Please assist.
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Re: M26-24 [#permalink]
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22 Aug 2015, 05:00
WillGetIt wrote: Dear Buenel,
You have mentioned in the solution that
5x+20 is the "sum of five smallest" but isn't it the "Sum of five Largest" because we are dealing with negative numbers (i.e. X is negative)
If this is the case then the answer would be -175.
Please assist. Our 7 consecutive odd integers are: \(x\), \(x+2\), \(x+4\), \(x+6\), \(x+8\), \(x+10\), \(x+12\). Let me ask you a question, which 5 of them are the smallest? Aren't those \(x\), \(x+2\), \(x+4\), \(x+6\) and \(x+8\)? What difference does it make whether x is negative or positive??
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Re: M26-24 [#permalink]
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08 Jul 2016, 07:59
Raihanuddin wrote: Average of largest 5 = -185/5 =-37
So the largest numbers are -41, -39, -37, -35, -33
Now if we consider smallest 5, we have to eliminate last 2 numbers, which are -35 and -33
Notice here that the numbers are equally spaced.
So the average of smallest number will just shift 2 place to the left.
Avg= -41
Therefore, total = -41*5= -205 Brilliant  Liked your approach !
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Re: M26-24 [#permalink]
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13 Sep 2016, 08:56
A relatively easier method to lessen calculation: Let the consecutive odd numbers be n-6, n-4, n-2, n, n+2, n+4, n+6 Given, n-2 + n + n+2 + n+4 + n+6 = -185 => 5n = -195 Therefore, n-6 + n-4 + n-2 + n + n+2 = 5n -10 = -195 - 10 = -205. Thus solved
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Re: M26-24 [#permalink]
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27 Oct 2016, 09:58
we can have another approach. If we question how many number is added in terms of number line, we will get 12 (largest-lowest) and 8 (2nd largest-2nd lowest). so in total 20 will be added and since all are negative number so the sum will be (-185-20)= -205
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here sum is negative right.means Sum of largest number should not be last 5 but a,a+4,........Then answer is -165 Where am I wrong??? I mean clearly a is negative,and in negative numbers smaller is larger.Please reply ??
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Re: M26-24 [#permalink]
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29 Mar 2017, 23:06
soniyanibhani wrote: here sum is negative right.means Sum of largest number should not be last 5 but a,a+4,........Then answer is -165 Where am I wrong??? I mean clearly a is negative,and in negative numbers smaller is larger.Please reply ?? The integers are: {x, x+2, x+4, x+6, x+8, x+10, x+12} = {-45, -43, -41, -39, -37, -35, -33}. The five largest there are {x+4, x+6, x+8, x+10, x+12} = {-41, -39, -37, -35, -33}. The sum = -185. The five smallest there are {x, x+2, x+4, x+6, x+8} = {-45, -43, -41, -39, -37}. The sum = -205. Hope it's clear.
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Re: M26-24 [#permalink]
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30 Mar 2017, 00:40
Bunuel wrote: soniyanibhani wrote: here sum is negative right.means Sum of largest number should not be last 5 but a,a+4,........Then answer is -165 Where am I wrong??? I mean clearly a is negative,and in negative numbers smaller is larger.Please reply ?? The integers are: {x, x+2, x+4, x+6, x+8, x+10, x+12} = {-45, -43, -41, -39, -37, -35, -33}. The five largest there are {x+4, x+6, x+8, x+10, x+12} = {-41, -39, -37, -35, -33}. The sum = -185. The five smallest there are {x, x+2, x+4, x+6, x+8} = {-45, -43, -41, -39, -37}. The sum = -205. Hope it's clear. Oh yes.I got it. Thanks a lot. I am so fool.
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Re: M26-24 [#permalink]
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18 Jul 2017, 02:42
Why I am not getting the same answer if I take the series 2n+1, 2n+3, 2n+5....., 2n+13 Given 5 largest sum, so that will be from 2n+5 to 2n+13 10n+45 = -185 n = 22 Asked - Sum of first five, so that will from 2n+1 to 2n+9 10n + 25 = -195 Bunuel please clarify
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I used easy numbers to plug in and solve. I started at -1,-3,-5,-7,-9,-11,-13. The smallest 5 numbers are -1,-3,-5,-7,-9. The largest 5 numbers are -5,-7,-9,-11,-13. Therefore, -1,-3 and -11,-13 are the only different numbers in those two sets. The difference between those 4 numbers are 20. Then I just add 20 to 185 and I got 205. Done.
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