To determine how many ways we can choose a committee of 4 from a group of 8 people, we can use the concept of combinations. Combinations are used when the order of selection does not matter.
The formula for combinations is given by:
C(n, k) = n! / (k! * (n – k)!)
Where:
- n is the total number of items (in this case, 8 people).
- k is the number of items to choose (in this case, 4 people).
In our scenario:
n = 8 and k = 4
Plugging in the values, we have:
C(8, 4) = 8! / (4! * (8 – 4)!)
This simplifies to:
C(8, 4) = 8! / (4! * 4!)
Calculating this step-by-step:
- 8! = 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1
- 4! = 4 × 3 × 2 × 1 = 24
Now we can simplify:
C(8, 4) = (8 × 7 × 6 × 5) / (4 × 3 × 2 × 1)
Calculating the numerator:
8 × 7 = 5656 × 6 = 336336 × 5 = 1680
And for the denominator:
4 × 3 = 1212 × 2 = 24
Putting it all together:
C(8, 4) = 1680 / 24 = 70
So, there are 70 different ways to form a committee of 4 people from a group of 8.