All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Just Math
Prime Mean (Posted on 2013-04-17) Difficulty: 3 of 5
At the end of a soccer season, every player on a team scored a prime number of goals, and the average for the team as a whole was also a prime number. No player’s tally was equal to another’s, and no player’s tally was the same as the average.

Given that nobody scored more than 45 goals, how many goals did each player score?

*** There are 11 players in a soccer team.

See The Solution Submitted by K Sengupta    
Rating: 4.2500 (4 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution the computer method | Comment 3 of 5 |

The largest prime not exceeding 45 is the 14th prime, 43, so to get the total of all the players' scores we just need the total of the first 14 primes and subtract out three of these primes.  
  
  
   10      for I=1 to 14:First14=First14+prm(I):next
   20      for LeaveOut1=1 to 12
   30        for LeaveOut2=LeaveOut1+1 to 13
   40          for LeaveOut3=LeaveOut2+1 to 14
   90             Sum=First14-prm(LeaveOut1)-prm(LeaveOut2)-prm(LeaveOut3)
  100             Avg=Sum//11
  110             if Avg=int(Avg) then if prmdiv(Avg)=Avg then
  120                  :if Avg=prm(LeaveOut1) or Avg=prm(LeaveOut2) or Avg=prm(LeaveOut3) then
  150                  :for I=1 to 14
  160                   :if I<>LeaveOut1 and I<>LeaveOut2 and I<>LeaveOut3 then
  170                             :print prm(I);:endif
  180                  :next
  190                  :print:print Avg
  200      next:next:next

which finds these individual players' scores

 5  7  11  13  17  19  29  31  37  41  43
 
which average

 23


  Posted by Charlie on 2013-04-17 12:37:57
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (5)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (7)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information