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A biased dice is thrown.
Here are the probabilities of each score.
Score
1
2
3
4
5
6
Probability
0.15
0.05
0.25
0.05
0.3
0.2
The dice is thrown 300 times.
Work out the expected number of times the score will be odd.

Answer :

Given:

A biased dice is thrown 300 times.

Table of probabilities of each score.

To find:

The expected number of times the score will be odd.

Solution:

Odd numbers on the dice are 1, 3, 5. The sum of their probability is

[tex]0.15+0.25+0.3=0.7[/tex]

Even numbers on the dice are 2, 4, 6. The sum of their probability is

[tex]0.05+0.05+0.2=0.3[/tex]

Now, the expected number of times the score will be odd is

[tex]\text{Expected odd number}=300\times \text{Probability of getting an odd number}[/tex]

[tex]\text{Expected odd number}=300\times 0.7[/tex]

[tex]\text{Expected odd number}=210[/tex]

Therefore, the expected number of times the score will be odd is 210.

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