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On 3 sales John has received commissions of $240, $80, and $110, and
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10 Jan 2014, 07:06
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On 3 sales John has received commissions of $240, $80, and $110, and he has 1 additional sale pending. If John is to receive an average (arithmetic mean) commission of exactly $150 on the 4 sales, then the 4th commission must be (A) $164 (B) $170 (C) $175 (D) $182 (E) $185 Problem Solving Question: 32 Category: Arithmetic Statistics Page: 66 Difficulty: 600 The Official Guide For GMAT® Quantitative Review, 2ND Edition
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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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10 Jan 2014, 07:06
SOLUTIONOn 3 sales John has received commissions of $240, $80, and $110, and he has 1 additional sale pending. If John is to receive an average (arithmetic mean) commission of exactly $150 on the 4 sales, then the 4th commission must be(A) $164 (B) $170 (C) $175 (D) $182 (E) $185 \(\frac{240+80+110+x}{4}=150\) > solving for x gives: x=170. Answer: B.
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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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10 Jan 2014, 11:03
Bunuel wrote: The Official Guide For GMAT® Quantitative Review, 2ND EditionOn 3 sales John has received commissions of $240, $80, and $110, and he has 1 additional sale pending. If John is to receive an average (arithmetic mean) commission of exactly $150 on the 4 sales, then the 4th commission must be (A) $164 (B) $170 (C) $175 (D) $182 (E) $185 Instead of adding all and making calculation messy, lets work on difference. We need to have 150 as average, so 1st value = +90 2nd value = 70 3rd value = 40 adding all the difference = 20, so the 4th value should compensate for 20 by adding +20 to 150 which is 170. Option B)



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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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07 Aug 2014, 02:51
Bunuel wrote: The Official Guide For GMAT® Quantitative Review, 2ND EditionOn 3 sales John has received commissions of $240, $80, and $110, and he has 1 additional sale pending. If John is to receive an average (arithmetic mean) commission of exactly $150 on the 4 sales, then the 4th commission must be (A) $164 (B) $170 (C) $175 (D) $182 (E) $185 Problem Solving Question: 32 Category: Arithmetic Statistics Page: 66 Difficulty: 600 GMAT Club is introducing a new project: The Official Guide For GMAT® Quantitative Review, 2ND Edition  Quantitative Questions ProjectEach week we'll be posting several questions from The Official Guide For GMAT® Quantitative Review, 2ND Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution. We'll be glad if you participate in development of this project: 1. Please provide your solutions to the questions; 2. Please vote for the best solutions by pressing Kudos button; 3. Please vote for the questions themselves by pressing Kudos button; 4. Please share your views on difficulty level of the questions, so that we have most precise evaluation. Thank you! Just observe the numbers provided All commissions are multiples of 10; average is also multiple of 10 So the 4th commission would also be multiple of 10 Only 170 fits in Answer = B



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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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05 Jul 2016, 04:54
[quote="Bunuel"] The Official Guide For GMAT® Quantitative Review, 2ND EditionOn 3 sales John has received commissions of $240, $80, and $110, and he has 1 additional sale pending. If John is to receive an average (arithmetic mean) commission of exactly $150 on the 4 sales, then the 4th commission must be (A) $164 (B) $170 (C) $175 (D) $182 (E) $185 Problem Solving Question: 32 Category: Arithmetic Statistics Page: 66 Difficulty: 600 GMAT Club is introducing a new project: The Official Guide For GMAT® Quantitative Review, 2ND Edition  Quantitative Questions ProjectEach week we'll be posting several questions from The Official Guide For GMAT® Quantitative Review, 2ND Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution. We'll be glad if you participate in development of this project: 1. Please provide your solutions to the questions; 2. Please vote for the best solutions by pressing Kudos button; 3. Please vote for the questions themselves by pressing Kudos button; 4. Please share your views on difficulty level of the questions, so that we have most precise evaluation. Thank you! [/quote) (140+50+240+x)/(4)=150 600=430+x x=170



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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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05 Jul 2016, 06:48
B170
one more method:TAKING RELATIVES
take avg =150
so $240is +90 more than average, $80is 70 less than average , and $110 is 40 less than average
so in total=+907040=20
so in order to compensate we need 20 more than the average we took for relative measure i.e 150,
so answer=150+20=170
hope it helps



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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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16 Jan 2018, 10:58
Bunuel wrote: On 3 sales John has received commissions of $240, $80, and $110, and he has 1 additional sale pending. If John is to receive an average (arithmetic mean) commission of exactly $150 on the 4 sales, then the 4th commission must be
(A) $164 (B) $170 (C) $175 (D) $182 (E) $185 240 + 80 + 110 + x = 150*4 Or, 430 + x = 600 So, x = 170, answer will be (B)
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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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06 Feb 2019, 05:08
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Re: On 3 sales John has received commissions of $240, $80, and $110, and
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