In a survey of a TriDelt chapter with 50 members, 23 were taking mathematics, 32 were taking English, and 9 were taking both. How many were not taking either of these subjects?
The number of people taking something is
23+32-9
So, that leaves how many taking nothing?
To solve this problem, we need to use the principle of inclusion-exclusion. We start by adding the number of members taking mathematics (23) to the number of members taking English (32), which gives us 23 + 32 = 55.
However, this count includes those who are taking both mathematics and English. Since we only want to count each person once, we need to subtract the number of members taking both subjects (9) from the total count. So, we subtract 9 from our previous count of 55:
55 - 9 = 46
Therefore, there are 46 members who are taking either mathematics or English or both.
To find those who are not taking either of these subjects, we subtract this count from the total number of members in the TriDelt chapter (50):
50 - 46 = 4
Therefore, there are 4 members who are not taking either mathematics or English.