The Probability that a pen manufactured by a company will be defective is 1/10.
If 12 such pens are manufactured, find the probability that
(i) exactly two will be defective (ii) at least two will be defective
Answers
Step-by-step explanation:
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's metabolic activities.
Probability that Exactly two will be defective is about 0.23
Probability that at least two will be defective is about 0.341
Given:
- Probability of defective pen = 1/10
- 12 Such Pens manufactured
To Find:
- Probability that
- (i) exactly two will be defective
- (ii) at least two will be defective
Solution:
P(x) = ⁿCₓpˣ(1-p)ⁿ⁻ˣ
n = 12
p = 1/10
1 - p = 1- 1/10 = 9/10
Step 1:
Probability that Exactly two will be defective P(2)
P(2) = ¹²C₂(1/10)²(9/10)¹²⁻²
P(2) = 66 * 9¹⁰ / 10¹²
P(2) ≈ 0.23
Step 2:
Probability that at least two will be defective 1 - P(0) - P(1)
P(0) = ¹²C₀(1/10)⁰(9/10)¹²⁻⁰
P(1) = ¹²C₁(1/10)¹(9/10)¹²⁻¹
1 - P(0) - P(1) ≈ 0.341
Probability that Exactly two will be defective is about 0.23
Probability that at least two will be defective is about 0.341