Some students are playing some sports on a playground. 35% of the students are playing cricket, 25% of the students are playing football, and 10% of the students only play both cricket and football. 48 Students are playing any other sport while 10% of students do not play any sport. So how many students only play football on the field?
Some students are playing some sports on a playground. 35% of the students are playing cricket, 25% of the students are playing football, and 10% of the students only play both cricket and football. 48 Students are playing any other sport while 10% of students do not play any sport. So how many students only play football on the field? Correct Answer 18
Given:
Playing cricket = 35%
Playing football = 25%
Play both cricket and football = 10%
10% of students do not play any sport
48 Students are playing any other sport
Formula used:
Total number ⇒ n (A ∪ B) = n (A) + n (B) - n (A∩ B)
Where n (A) = the number of elements in set A.
Calculation:
Let the total number of students be x.
35% of the students are playing cricket
Then, the number of students who playing cricket = 35% of x
⇒ (35 / 100) × x = 7x / 20
25% of the students are playing football
Then, the number of students who playing football = 25% of x
⇒ (25 / 100) × x = x / 4
10% of the students only play both cricket and football
Then, the number of students who only play both cricket and football = 10% of x
⇒ (10 / 100) × x = x / 10
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Total number of students who play cricket and football
By formula,
⇒ (7x / 20) + (x / 4) - (x / 10) = x / 2
10% of students do not play any sport
Then, the number of students who do not play any sport = 10% of x
⇒ (10 / 100) × x = x / 10
Now the number of remaining students who play other sports
⇒ x - (x / 2) - (x / 10) = 2x / 5 ---(i)
But by the question, the number of remaining students who play other sports = 48 ---(i)
Now by equation (i) and (ii), we get
⇒ 2x / 5 = 48
⇒ x = 120
Now the number of students who play only football
⇒ (the number of students who playing football) - (the number of students who only play both cricket and football)
⇒ (x / 4) - (x / 10) = 3x / 20
Now put the value of x and we get
⇒ (3 / 20) × 120 = 18
∴ The number of students who play only football is 18.
Alternate method:
By percentage:
Let the total students be 100%.
By n (A ∪ B) = n (A) + n (B) - n (A∩ B)
Total number of students who play cricket and football
⇒ 35 + 25 - 10 = 50%
[ alt="F1 Sachin Shraddha 05.09.2020 D 4" src="//storage.googleapis.com/tb-img/production/20/09/F1_Sachin_Shraddha_05.09.2020_D%204.png" style="width: 183px; height: 141px;">
10% students do not play any sport
Now the number of remaining student who play other sports
⇒ 100 - 50 - 10 = 40%
But by question, then
⇒ 40% = 48 then 100% = (48 / 40) × 100 = 120 students
Now the number of student who play only football
⇒ (the number of students who playing football) - (the number of students who only play both cricket and football)
⇒ 25 - 10 = 15%
⇒ 15% of 120
⇒ (15 / 100) × 120 = 18
∴ The number of student who play only football is 18.