If result of all the matches are interchanged i.e goals for will become goals conceded and vice versa then how many teams will have same number of goals scored as before?

Since total number of goals scored and goals against is same hence we can find goals against Marconi which is (11 + 9 + 5 + 1 + 7 + 4) ? (5 + 9 + 7 + 4 + 5) = 37 ? 30 = 7. Since Bose sadan scored 11 goals while goals against is 5 it is possible when all the matches are won with (3-1) (4-2) and (4-2)
Since Marconi got 4 points which is possible with 1 win (3 points) 1 draw (1 point) and 1 loss (0 point) Similarly Rankin got 3 points and also Goals for is 4 and against is 5 so all three matches can not end with draw (It is when goals for is equal to goals against) so 3 points is possible with 1 win and 2 loss.
Faraday scored only 1 goal, goal against is 4 and won 1 match it is possible only when he won by (1-0) and lost two matches with (0-2) each[ as with the combination (0-1) and (0-3) is not possible since (0-3) goal difference is 3] Since Edison won on Wednesday with (2-0) and total goals for is 5 while against is 7, so in other two game it lost with (2-4) and (1-3)
Draw is casued only with Diesel and Marconi hence they must have played with each other and the match was tie.
On Monday Diesel played with Bose, on Tuesday Diesel played with Edison while on Wednesday Diesel played with Marconi.
On Wednesday Bose must have played with Marconi
Faraday played against Edison on Wednesday and lost with (0-2)
Marconi played against Faraday on Monday while against Bose on Tuesday.
Since Rankin scored 4 goals and conceded 5 goals result of Bose and Rankin (3-1) similarly result of Rankin and Edison (3 ? 1)
Now we can conclude that Bose sadan won against Diesel and Marconi with (4-2) and (4-2) Diesel won against Edison with (4-2)
So matches on Monday:
So final result
Number of points are as follows: Bose (3 + 3 + 3 = 9), Diesel (0 + 3 + 1 = 4), Edison (0 + 0 + 3 = 3), Faraday (0 + 3 + 0 = 3), Marconi (3 + 0 + 1 = 4), and Rankin (3 + 0 + 0 = 3)
From the table Diesel team won against Edison.

Maria Sharapova, seed 1, would meet the winner of the match between seed 8 and seed 9, but it is given that Serena Williams, seed 8 lost against seed 9 Nadia Petrovain the second round. Hence Nadia Petrova (seed 9).

All odd numbered seeds up to 15 reach the 2nd round while instead of seeds 2 to 16 the players who reach the second round are seeds 31, 29, 27, 25, 23, 21, 19 and 17.
The second round matches are between seeds 1-17, 31-15, 3-19, 29-13, 5-21, 27-11, 7-23 and 25-9. Since there are no upsets in that round the winners are seeds 1, 15, 3, 13, 5, 11, 7 and 9.
The quarter final line up would be
1-9, 15-7, 3-11 and 13-5.
If seed 13 wins her match in the quarters she will next meet seed 1, i.e. Maria Sharapova in semifinals.

If the top eight seeds make it to quarterfinals, then from the table we can find that Sharapova being top seed will meet seed 8 in the quarterfinals, and in the semifinals she will meet the winner of the match between seeds 4 and 5. So she will not meet seeds 4, 5 or 8 in the finals.
We can sum up the given information as below:
(ii) No team plays against the same team more than once
(iv) No ties permitted.
As per the information given for stage I, we can conclude and draw the table that
(a) As B lost at least one match, hence A won all the 3 matches.
(b) The two teams who lost all the matches cannot be A (as it won all 3 matches), cannot be B (since it is given that E lost to B), cannot be D (since D won against C & F). Hence, the two teams must be C and F.
(c) F did not play against the top team (i.e. A).
We can tabulate all the information as :
In the given below table a blank space means there was no match in this stage (i.e there was no match between A and E in this stage), Result of a match for a team is shown in its row,
(d) A lost both its matches against E and F.
(e) F won against A, hence is the bottom team (out of C and F) which won both the matches F won against C as well. This also means that C lost both its matches against B and F.
(f) Apart from A and C, one more team lost both the matches in Stage-II. That team can neither be E (since A lost to E), nor B (since C lost to B), nor F (as F won both its matches). Hence, the team must be D.

1^st let us understand the concept of the tournament.
Try to understand the table, in the 1^st round the sum of seed is always 33, the same for round 2 is 17 and so on considering there is no upset.
Lindsay Davenport (Seed 2) was scheduled to to meet seed 7, i.e., Justine Henin in the quarter finals. But in the second round since match 7 - involving seed 7 (Justine Henin) and seed 10 (Venus Williams) - resulted in an upset and Venus Williams won the game, hence Davenport will meet Venus Williams in the quarter finals.

Since total number of goals scored and goals against is same hence we can find goals against Marconi which is (11 + 9 + 5 + 1 + 7 + 4) ? (5 + 9 + 7 + 4 + 5) = 37 ? 30 = 7. Since Bose sadan scored 11 goals while goals against is 5 it is possible when all the matches are won with (3-1) (4-2) and (4-2)
Since Marconi got 4 points which is possible with 1 win (3 points) 1 draw (1 point) and 1 loss (0 point) Similarly Rankin got 3 points and also Goals for is 4 and against is 5 so all three matches can not end with draw (It is when goals for is equal to goals against) so 3 points is possible with 1 win and 2 loss.
Faraday scored only 1 goal, goal against is 4 and won 1 match it is possible only when he won by (1-0) and lost two matches with (0-2) each[ as with the combination (0-1) and (0-3) is not possible since (0-3) goal difference is 3] Since Edison won on Wednesday with (2-0) and total goals for is 5 while against is 7, so in other two game it lost with (2-4) and (1-3)
Draw is casued only with Diesel and Marconi hence they must have played with each other and the match was tie.
On Monday Diesel played with Bose, on Tuesday Diesel played with Edison while on Wednesday Diesel played with Marconi.
On Wednesday Bose must have played with Marconi
Faraday played against Edison on Wednesday and lost with (0-2)
Marconi played against Faraday on Monday while against Bose on Tuesday.
Since Rankin scored 4 goals and conceded 5 goals result of Bose and Rankin (3-1) similarly result of Rankin and Edison (3 ? 1)
Now we can conclude that Bose sadan won against Diesel and Marconi with (4-2) and (4-2) Diesel won against Edison with (4-2)
So matches on Monday:
So final result :
Number of points are as follows: Bose (3 + 3 + 3 = 9), Diesel (0 + 3 + 1 = 4), Edison (0 + 0 + 3 = 3), Faraday (0 + 3 + 0 = 3), Marconi (3 + 0 + 1 = 4), and Rankin (3 + 0 + 0 = 3)
Total number of matches is 9, out these 9 matches, the matches that end with goal difference of 2 is Monday: all the three matches, Tuesday 2 matches and Wednesday 2 matches so required percentage is 7 × 100/9 = 77.77%

Since total number of goals scored and goals against is same hence we can find goals against Marconi which is (11 + 9 + 5 + 1 + 7 + 4) ? (5 + 9 + 7 + 4 + 5) = 37 ? 30 = 7. Since Bose sadan scored 11 goals while goals against is 5 it is possible when all the matches are won with (3-1) (4-2) and (4-2)
Since Marconi got 4 points which is possible with 1 win (3 points) 1 draw (1 point) and 1 loss (0 point) Similarly Rankin got 3 points and also Goals for is 4 and against is 5 so all three matches can not end with draw (It is when goals for is equal to goals against) so 3 points is possible with 1 win and 2 loss.
Faraday scored only 1 goal, goal against is 4 and won 1 match it is possible only when he won by (1-0) and lost two matches with (0-2) each[ as with the combination (0-1) and (0-3) is not possible since (0-3) goal difference is 3] Since Edison won on Wednesday with (2-0) and total goals for is 5 while against is 7, so in other two game it lost with (2-4) and (1-3)
Draw is caused only with Diesel and Marconi hence they must have played with each other and the match was tie.
On Monday Diesel played with Bose, on Tuesday Diesel played with Edison while on Wednesday Diesel played with Marconi.
On Wednesday Bose must have played with Marconi
Faraday played against Edison on Wednesday and lost with (0-2)
Marconi played against Faraday on Monday while against Bose on Tuesday.
Since Rankin scored 4 goals and conceded 5 goals result of Bose and Rankin (3-1) similarly result of Rankin and Edison (3 ? 1)
Now we can conclude that Bose sadan won against Diesel and Marconi with (4-2) and (4-2) Diesel won against Edison with (4-2)
So matches on Monday:
So final result
Number of points are as follows: Bose (3 + 3 + 3 = 9), Diesel (0 + 3 + 1 = 4), Edison (0 + 0 + 3 = 3), Faraday (0 + 3 + 0 = 3), Marconi (3 + 0 + 1 = 4), and Rankin (3 + 0 + 0 = 3)
Since total number of points is 26 so number of points more than 2.6 but less than 5.2 is (i.e points 3. 4, 5) 5.

Since total number of goals scored and goals against is same hence we can find goals against Marconi which is (11 + 9 + 5 + 1 + 7 + 4) ? (5 + 9 + 7 + 4 + 5) = 37 ? 30 = 7. Since Bose sadan scored 11 goals while goals against is 5 it is possible when all the matches are won with (3-1) (4-2) and (4-2)
Since Marconi got 4 points which is possible with 1 win (3 points) 1 draw (1 point) and 1 loss (0 point) Similarly Rankin got 3 points and also Goals for is 4 and against is 5 so all three matches can not end with draw (It is when goals for is equal to goals against) so 3 points is possible with 1 win and 2 loss.
Faraday scored only 1 goal, goal against is 4 and won 1 match it is possible only when he won by (1-0) and lost two matches with (0-2) each[ as with the combination (0-1) and (0-3) is not possible since (0-3) goal difference is 3] Since Edison won on Wednesday with (2-0) and total goals for is 5 while against is 7, so in other two game it lost with (2-4) and (1-3)
Draw is casued only with Diesel and Marconi hence they must have played with each other and the match was tie.
On Monday Diesel played with Bose, on Tuesday Diesel played with Edison while on Wednesday Diesel played with Marconi.
On Wednesday Bose must have played with Marconi
Faraday played against Edison on Wednesday and lost with (0-2)
Marconi played against Faraday on Monday while against Bose on Tuesday.
Since Rankin scored 4 goals and conceded 5 goals result of Bose and Rankin (3-1) similarly result of Rankin and Edison (3 ? 1)
Now we can conclude that Bose sadan won against Diesel and Marconi with (4-2) and (4-2) Diesel won against Edison with (4-2)
So matches on Monday:
So final result
Number of points are as follows: Bose (3 + 3 + 3 = 9), Diesel (0 + 3 + 1 = 4), Edison (0 + 0 + 3 = 3), Faraday (0 + 3 + 0 = 3), Marconi (3 + 0 + 1 = 4), and Rankin (3 + 0 + 0 = 3)
Out of 9 matches only 1 match end up with tie so total number of points is 8 × 3 + 2 = 26

Each match has 4 points and each team plays 4 matches. Hence total number of points is 40
Paraguay wins all matches. So it scores 3 x 4 = 12 points.
Turkey loses all matches. So it scores 1 x 4 = 4 points.
16 points are scored by Turkey and Paraguay
The other teams score 40 - 16 = 24 points
As all other teams score equal points, each team scores 24/3 = 8 points

The total score is 40 points. If each team scores equally, each team scores 40/5 = 8 points