Question

A bag contains only red, green, brown and yellow marbles. The probabilities of selecting each colour are shown below. Colour Red Green Brown Yellow Probability 0.2 0.3 x 0.1 Find the probability of selecting a brown marble.

Answer 1

0.4

Explanation:

Given that:

Probability of :

Red _____Green ___ Brown _____ Yellow

0.2 ______ 0.3 ______ X ________ 0.1

Since the bag contains only red, green, brown and yellow marbles ;

The sum of each color's probability should sum up to 1;

ΣP(x) = 1

Hence,

0.2 + 0.3 + x + 0.1 = 1

0.6 + x = 1

x = 1 - 0.6

x = 0.4

P(brown) = 0.4