In a survey of 40 students in a class 19 have visited Lagos and 17 have visited benin city. If 13 have visited neither. How many students have visited?
1. Both cities
2. Benin city but not Lagos
To find the number of students who have visited both cities, you need to subtract the number of students who have visited neither from the total number of students.
Total number of students = 40
Number of students who have visited neither = 13
So, the number of students who have visited either Lagos or Benin City = 40 - 13 = 27
Now, let's find the number of students who have visited both cities:
Number of students who have visited Lagos = 19
Number of students who have visited Benin City = 17
Number of students who have visited both cities = Number of students who have visited Lagos + Number of students who have visited Benin City - Number of students who have visited either Lagos or Benin City
= 19 + 17 - 27
= 36 - 27
= 9
Therefore,
1. 9 students have visited both cities.
2. To find the number of students who have visited Benin City but not Lagos, we subtract the number of students who have visited both cities from the number of students who have visited Benin City.
Number of students who have visited Benin City but not Lagos = Number of students who have visited Benin City - Number of students who have visited both cities
= 17 - 9
= 8
Therefore, 8 students have visited Benin City but not Lagos.