A college awarded 38 medals in football, 15 in basketball and 20 in cricket. If these medals went to a total of 58 men and only three men got medals in all the three sports, how many received medals in exactly one of the three sports?
Answers
Answer:
If these medals went to a total of 58 men and only 3 men got medals in all the three sports, how many received medals in exactly two of the three ... Example 34 - Chapter 1 Class 11 Sets
Solution :
Let,
V = set of students getting medals in volleyball
F = set of students getting medals in football
B = set of students getting medals in basket ball
We are given the following:
n ( V ) = 38,
n ( F ) = 15
n ( B ) = 20
n ( V U F U B ) = 58
n ( V ∩ F ∩ B ) = 3
Let,
a = Number of students getting medals in volleyball and football but not the basketball
b = Number of students getting medals in football and basketball but not volleyball
c = Number of students getting medals in basketball and volleyball but not football
So,
n ( V U F U B ) is as follows :
⇒ [ 38 - ( a + c + 3 ) ] + [ 15 - ( a + b + 3 ) ] + [ 20 - ( b + c + 3 ) ] + a + b + c = 58
⇒ 67 - ( a + b + c ) = 58
⇒ a + b + c = 9
∴ Number of players who received medals in exactly two of the three sports,
⇒ a + b + c
⇒ 9
∴ Number of players who received medals in exactly two of the three sports is 9 respectively.