Question

the probability he chooses get marbel

Answer 1

Step 1: Problem

Step 2: Concept

$\text{Probability of any event = }\frac{n\text{ umber of required outcome}}{n\text{ umber of total possible outcome}}$

Step 3: Method

Red R = 3

Blue B = 2

Green G = 5

Total = 10

Apply tree diagram

Probability of choosing a red marble without replacement then a blue marble = Red, and Blue

'AND' in probability mean multiplication.

$\begin{gathered} =\text{ }\frac{3}{10\text{ }}\text{ x }\frac{2}{9} \\ =\text{ }\frac{6}{90} \\ =\text{ }\frac{1}{15} \end{gathered}$

Step 4: Final answer

Probability of choosing a red marble without replacement then a blue marble = 1/15