In a college, out of 850 students, 230 play cricket; 250 hockey, and 360 basketball. Of the total, if 75 play both basketball and hockey; 68 play cricket and basketball; 37 play cricket and hockey; and 30 play all three games, how many students don't play any games at all?
In a college, out of 850 students, 230 play cricket; 250 hockey, and 360 basketball. Of the total, if 75 play both basketball and hockey; 68 play cricket and basketball; 37 play cricket and hockey; and 30 play all three games, how many students don't play any games at all? Correct Answer 160
Formula used:
If A, B, and C are finite sets, then
n(A ∪ B ∪ C) = n(A) + n(B) + n(C) - n(A ∩ B) - n(B ∩ C) - n(A ∩ C) + n(A ∩ B ∩ C)
n(A ∪ B ∪ C) = Number of students play at least one game
Calculation:
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According to the question
n(A ∪ B ∪ C) = n(A) + n(B) + n(C) - n(A ∩ B) - n(B ∩ C) - n(A ∩ C) + n(A ∩ B ∩ C)
⇒ 230 + 360 + 250 - 68 - 75 - 37 + 30
⇒ 870 - 180 = 690
Number of students who don't play any games = 850 - 690
⇒ 160
∴ The number of students who don't play any games is 160.