Question

A marble is drawn from a random bag that contains 3green 4yellow 5 blue and 8pink marbles what’s the probability that the marble drawn will be green or blue?

Answer 1

Green:
`\bf~(3)/(20)`

Blue:
`\bf~(5)/(20)` or
`\bf~(1)/(4)`

Combined probability of a green or a blue:
`\bf~(8)/(20)` or
`\bf~(2)/(5)`

Explanation:

The probabilty of you getting a marble of a given colour is the amount of marbles of the given colour divided by the total amount of marbles.

By using that rule, we get a probabilty o
`(3)/(20)` for a green marble, a probabilty of
`(1)/(4)` for a blue marble, or if we sum those two and find the probabilty of getting a marble that is either green or blue, we get
`(2)/(5)`

`(3)/(20) + (5)/(20) = (8)/(20) = (4)/(5)`

Hope it helped,

BioTeacher101