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by hey_thr67 » Tue Jun 19, 2012 1:23 am
Average goals scored by 15 selected players in EPL is 16.Maximum goals scored by a player is 20 and minimum is 12. Goals scored by players is between 12 and 20.What can be maximum number of players who scored at least 18 goals ?

A: 10
B: 5
C: 9
D: 6
E: 11
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by GMATGuruNY » Tue Jun 19, 2012 3:27 am
hey_thr67 wrote:Average goals scored by 15 selected players in EPL is 16.Maximum goals scored by a player is 20 and minimum is 12. Goals scored by players is between 12 and 20.What can be maximum number of players who scored at least 18 goals ?

A: 10
B: 5
C: 9
D: 6
E: 11
Total number of goals = (number of players)(average number of goals) = 15*16 = 240.

We can plug in the answers, which represent the MAXIMUM number of players who score at least 18 goals.
When the question asks for the MAXIMUM possible value, the GREATEST answer choice is unlikely to be correct.
Thus, we should start with answer choice A, the second greatest answer choice.

To MAXIMIZE the number of players who score at least 18 goals, we must MINIMIZE the number of goals scored by each player.

Answer choice A: 10
Minimum number of goals scored by these 10 players = 10*18 = 180.
Minimum number of goals scored by the remaining 5 players = 5*12 = 60.
Minimum total = 180+60 = 240.
Success!

The correct answer is A.

[Please also see my post below, which interprets the question as does Anurag in his solution that follows.]
Last edited by GMATGuruNY on Tue Jun 19, 2012 8:25 am, edited 2 times in total.
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by Anurag@Gurome » Tue Jun 19, 2012 7:35 am
hey_thr67 wrote:Average goals scored by 15 selected players in EPL is 16. Maximum goals scored by a player is 20 and minimum is 12. Goals scored by players is between 12 and 20. What can be maximum number of players who scored at least 18 goals ?
We know that the maximum goal scored by a player is 20.
Hence, at least one player has scored 20 goals. To maximize the number of players who has scored at least 18 goals, we need to maximize the number of players who has scored exactly 18 goals. This is because if we maximize the number of players who has scored 19 or 20 goals, then automatically we will maximize the number of players who has scored less than 16 goals as the average number of goals scored by a player is 16.

Now to maximize the number of players who has scored exactly 18 goals, we have to minimize the number of goals scored by the rest of the players. Minimum possible goals a player can score is 12.

Let us assume n players has scored 18 goals and only one player has scored 20 goals. Hence, (15 - n - 1) = (14 - n) players has scored 12 goals each.

Therefore, (12*(14 - n) + 18*n + 20) = 15*16
--> (12*14 - 12n + 18n + 20) = 15*16
--> (18n - 12n) = (15*16 - 12*14 - 20)
--> 6n = (240 - 168 - 20) = 52
--> n = 8.(Something)

As the number of persons must be a whole number, maximum possible value of n is 8.

Therefore, number of players who has scored at-least 18 goals = (8 + 1) = 9

The correct answer is C.
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by GMATGuruNY » Tue Jun 19, 2012 8:05 am
hey_thr67 wrote:Average goals scored by 15 selected players in EPL is 16.Maximum goals scored by a player is 20 and minimum is 12. Goals scored by players is between 12 and 20.What can be maximum number of players who scored at least 18 goals ?

A: 10
B: 5
C: 9
D: 6
E: 11
Total number of goals = (number of players)(average number of goals) = 15*16 = 240.

Maximum goals scored by a player is 20 and minimum is 12.
The wording here is unclear.
My solution above assumed the following meaning: no player can score more than 20 goals, and no player can score fewer than 12 goals.
Anurag's solution above interprets the following meaning:
At least one player scores 20 goals, and at least one player scores 12 goals.

Assuming this interpretation, we could plug in the answers as follows.

When the question asks for the MAXIMUM possible value, the GREATEST answer choice is unlikely to be correct.
Thus, we should start with answer choice A, the second greatest answer choice.

To MAXIMIZE the number of players who score at least 18 goals, we must MINIMIZE the number of goals scored by every player besides the one who scores 20 goals.

Answer choice A: 10
Total goals scored by 1 player with 20 goals and 9 players with 18 goals each = 1*20 + 9*18 = 20+162 = 182.
Minimum number of goals scored by the remaining 5 players = 5*12 = 60.
Total goals = 182+60 = 242.
The total number of goals must be just a bit less, implying that the correct answer must be the next smallest option.

The correct answer is C.

Answer choice C: 9
Total goals scored by 1 player with 20 goals and 8 players with 18 goals each = 1*20 + 8*18 = 20+144 = 164.
Minimum number of goals scored by the remaining 6 players = 6*12 = 72.
Total goals = 164+72 = 236, which is below the threshold of 240.
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by singhumesh » Wed Jun 20, 2012 9:41 am
Average goals scored by 15 selected players in EPL is 16.Maximum goals scored by a player is 20 and minimum is 12. Goals scored by players is between 12 and 20.What can be maximum number of players who scored at least 18 goals ?

To my estimate , answer must be 11
20 +18x10 +12x2 + 16= 15x16=240

players who scored at least 18 goals =10(scored 18) +1(scored 20)=11

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by singhumesh » Wed Jun 20, 2012 9:42 am
Average goals scored by 15 selected players in EPL is 16.Maximum goals scored by a player is 20 and minimum is 12. Goals scored by players is between 12 and 20.What can be maximum number of players who scored at least 18 goals ?

To my estimate , answer must be 11
20 +18x10 +12x2 + 16= 15x16=240

players who scored at least 18 goals =10(scored 18) +1(scored 20)=11

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by Anurag@Gurome » Wed Jun 20, 2012 9:50 am
singhumesh wrote:To my estimate , answer must be 11
20 +18x10 +12x2 + 16= 15x16=240
You're one player short as (1 + 10 + 2 + 1) = 14
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by singhumesh » Wed Jun 20, 2012 11:41 am
Anurag@Gurome wrote:
singhumesh wrote:To my estimate , answer must be 11
20 +18x10 +12x2 + 16= 15x16=240
You're one player short as (1 + 10 + 2 + 1) = 14
Thanks anurag sir..
i missed one player

12+20+18x +m=240
x= 11 + (10-m)/18
if m=46 (15,15,16)or(14,15,17) or (14,16,16)
x=9