Question

In a sample survey of 645 people, it was found that 516 people have a high school certificate. If a person is chosen at random, what is the probability that he / she has a high school certificate?
(a) $\frac{1}{2}$

(b) $\frac{3}{5}$

(c) $\frac{7}{10}$

(d) $\frac{4}{5}$

Answer 1

Total number of people surveyed = 645

Number of people who have a high school certificate = 516

∴ P(Person has a high school certificate) = $\frac{\mathrm{Number}\mathrm{of}\mathrm{people}\mathrm{who}\mathrm{have}\mathrm{a}\mathrm{high}\mathrm{school}\mathrm{certificate}}{\mathrm{Total}\mathrm{number}\mathrm{of}\mathrm{people}\mathrm{surveyed}}=\frac{516}{645}=\frac{4}{5}$

Hence, the correct answer is option (d).