SOLUTION: There were two competitions in a puzzle tournament. The Sudoku competition had twice as many participants as the Crossword competition. If 225 people competed overall, and 60 of

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Question 1151451: There were two competitions in a puzzle tournament. The Sudoku competition
had twice as many participants as the Crossword competition. If 225 people
competed overall, and 60 of them participated in both competitions, how many
people participated in the Sudoku competition?

Found 2 solutions by Theo, jim_thompson5910:
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
x = number of sudoku competition players.
y = number of crossword competition players.
60 = number of participants in both competitions.

since the number of participants in both is included in the total of each, you have:

x + y - 60 = 225
x + y = 285
y = 2x
3x = 285
x = 95
y = 190

you have 95 people who competed in the sudoku competition and 190 who competed in the crossword competition.

of the 95 who competed in the sudoku competition, 60 also competed in the crossword competition.

therefore, you have:
35 who competed only in the sudoku competition.
130 who competed only in the crossword competition.
60 who competed in both.

total who competed in both competitions is 35 + 130 + 60 = 225

the question is how many competed in the sudoku competition.

that would be 35 + 60 = 95.

the basic assumption is that the number who competed in both are counted in the number who competed in each.

that means they are being double counted and so one of them needs to be subtracted out.

that's why you get x + y - 60 = 225.

that becomes your basic equation that you use to solve for x and y, taking nto account that y = 2x.








Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

@Theo has the right idea for the most part, but mixed up the wording.

There are twice as many Sudoku players compared to Crossword players, so it should be x = 2y instead of y = 2x.

The solution values will be the same except you swap the values of x and y. So we have
x = 190
y = 95