105 students were asked if they liked soccer, rugby, or football. 4 liked only rugby, 40 liked rugby, 12 liked only rugby and football, 63 did not like football, 21 didn't like any, 16 liked only soccer and football, 60 liked soccer. How many liked only football? How many liked all three sports? How many liked football and rugby? How many liked football or rugby? I drew a Venn Diagram with 3 circles. When I label the regions without information with letters to solve for the information, I labeled the soccer only with a, the football only with b, the soccer and rugby intersection with c. How do I find the intersection of all 3? Should it be c+d or d-c or just d?

To find the intersection of all three sports (soccer, rugby, and football), you need to consider the regions that are not labeled in the Venn diagram. In this case, as you mentioned, you have labeled the regions without information with letters: soccer only with 'a,' football only with 'b,' and the soccer and rugby intersection with 'c.'

To find the intersection of all three, you need to solve for the value of 'd.' Region 'd' represents the individuals who like soccer, rugby, and football.

Let's break down the given information and use it to find the value of 'd':

1. 4 liked only rugby: This means 'a' (soccer only), 'b' (football only), and 'c' (soccer and rugby) are not affected. So, we still have to account for 'd.'

2. 12 liked only rugby and football: This affects 'b' (football only) and 'c' (soccer and rugby). Thus, 'd' remains unaffected.

3. 63 did not like football: This statement does not directly affect 'd.'

4. 21 didn't like any: This statement also doesn't directly affect 'd.'

5. 16 liked only soccer and football: This affects 'a' (soccer only) and 'b' (football only), but 'd' remains unaffected.

6. 60 liked soccer: This statement affects 'a' (soccer only), but 'd' remains unaffected.

Based on the given information, we can conclude that 'd' represents the individuals who like soccer, rugby, and football. Hence, the intersection of all three is simply represented by 'd.'

To find the value of 'd,' we need to calculate it based on the information provided. You can start by adding up the counts of labeled regions 'a,' 'b,' and 'c' and subtracting this sum from the total count of individuals who liked soccer, rugby, or football (105).

d = Total count - (a + b + c)
= 105 - (a + b + c)

To find the specific values for 'd,' 'b,' 'c,' and 'a,' you might need additional information or equations.

To find the intersection of all three categories (liking soccer, rugby, and football), we need to consider the information given about the Venn diagram. Let's go step-by-step:

Step 1: Define the regions with labels:
- Region with only soccer: a
- Region with only football: b
- Region with soccer and rugby: c

Step 2: Determine the values for the labeled regions:
- 105 students in total.
- 16 liked only soccer and football.
- 12 liked only rugby and football.
- 4 liked only rugby.
- 21 didn't like any sports.
- 63 didn't like football.
- 60 liked soccer.
- We need to find the number of students who liked only football (region b), the number who liked all three sports (intersection of all regions), and the number who liked football and rugby (intersection of regions b and c).

Step 3: Calculate the missing values:
- The total number of students who liked at least one sport is given by:
Total = a + b + c + (soccer and rugby only) + (soccer and football only) + (rugby and football only) + (all three)
105 = a + b + c + 4 + 16 + 12 + (all three)
105 = a + b + c + 32 + (all three)
(all three) = 105 - (a + b + c + 32)

- The number who liked football is given by:
Students who liked football = b + (rugby and football only) + (soccer and football only) + (all three)
105 = b + 12 + 16 + (all three)
105 = b + 28 + (all three)
b = 105 - 28 - (all three)

- The number who liked rugby and football is given by:
(rugby and football) = (rugby and football only) + (all three)
(rugby and football) = 12 + (all three)

Step 4: Simplify the expression for (all three):
- Substitute the value of b and (rugby and football only) from the above equations into the expression for (all three).
- (all three) = 105 - 28 - (all three)
- 2 * (all three) = 105 - 28
- (all three) = (105 - 28) / 2

Therefore, the intersection of all three regions is represented by the value (105 - 28) / 2.

Note: The diagram you drew may be slightly different. The regions, labels, and numbers given above are specific to the information provided in the question.