Manager
Joined: 05 Oct 2014
Posts: 133
Given Kudos: 229
Location: India
Concentration: General Management, Strategy
GMAT Date: 07-23-2015
GPA: 3.8
WE:Project Management (Energy and Utilities)
Re: If the average (arithmetic mean) of 4 numbers is 50, how man
[#permalink]
09 Nov 2019, 21:57
If the average (arithmetic mean) of 4 numbers is 50, how many of the numbers are greater than 50 ?
(1) None of the four numbers is equal to 50.
(2) Two of the numbers are equal to 25.
I attempted the question in 1:12 Mins and choose incorrect option B. However, after careful reading again, I thought the logic would be as below -
(1) says all the four nos are either >50 or <50. But dont know the answer. NOT SUFFICIENT.
(2) says, 2*25=50, Sum of balance two = 200-50=150. Now this is where I did wrong.I took an average of the balance two, 150/2=75 and considered B as the right answer.
However, after going through the question again, I found, no where it is written both the nos. are equal or not. Further I dont know any of the no, so that I can deduce the other no. So even though sum of both coming 150, it can be as 75+75, 40+110, 50+100.....etc.
(1) + (2) is out of question.
Thus E should be the correct answer choice.