A basketball player makes 80% of her free throws. Assuming each attempt is independent, what is the probability that she makes exactly 3 of her next 4 free throws?
Solution
Problem
A basketball player makes 80% of her free throws. Assuming each attempt is independent, what is the probability that she makes exactly 3 of her next 4 free throws?
Step 1: Recognize the binomial setting.
There are 4 independent attempts, each attempt has two outcomes, and the probability of success remains 0.80.
Use the binomial probability formula:
P(X = k) = C(n,k)p^k(1-p)^(n-k)
Step 2: Identify the values.
n = 4
k = 3
p = 0.80
1 - p = 0.20
Step 3: Substitute into the formula.
P(X = 3) = C(4,3)(0.80)^3(0.20)^1
Step 4: Evaluate the combination.
C(4,3) = 4
So:
P(X = 3) = 4(0.80)^3(0.20)
Step 5: Evaluate the powers and multiply.
(0.80)^3 = 0.512
P(X = 3) = 4(0.512)(0.20)
P(X = 3) = 0.4096
Therefore, the probability that she makes exactly 3 of the 4 free throws is 0.4096, or 40.96%.
Result
0.4096 or 40.96%