# Probability That Exactly 1 is Defective in Getting 2 Cell Phones

Date of Exam:

**Problem**

A box contains 5 defective and 195 non-defective cell phones. A quality control engineer selects 2 cell phones at random without replacement. What is the probability that exactly 1 is defective?

A. 0.0190 | C. 0.0390 |

B. 0.0490 | D. 0.0290 |

**Answer Key**

[ B ]

**Solution**

$P = \left( \dfrac{5}{200} \times \dfrac{195}{199} \right)(2)$

$P = 0.0490$

**Another Solution**

$P = \dfrac{(^5C_1)(^{195}C_1)}{^{200}C_2}$

$P = 0.0490$