2018-II-43

16-06-2021 app.cch No Comments

Ans: C
The required probability

$\begin{array}{cl} = & \frac{1}{6} + \frac{4}{6} \times \frac{4}{6} \times \frac{1}{6} + \frac{4}{6} \times \frac{4}{6} \times \frac{4}{6} \times \frac{4}{6} \times \frac{1}{6} + \dots \\ = & \frac{\frac{1}{6}}{1 - \frac{4}{6} \times \frac{4}{6}} \\ = & \frac{3}{10} \end{array}$

2018, HKDSE-MATH, Paper 2 Probability, Sequences

Same Topic:

Leave a Reply Cancel reply