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A single six sided dice is rolled. Find the probability of rolling an even number or a number less than four

User SakeSushiBig
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1 Answer

22 votes
22 votes
Answer:
Pr(even\text{ number or less number than 4\rparen = 5/6}

Step-by-step explanation:

Given:

A single 6-sided die is rolled

To find:

the probability of rolling an even number or a number less than four

To determine the probability, we will find the pr(rolling an even number) and the pr(rolling a number less than 4)

pr(rolling an even number) = number of even numbers/total numbers

even number = {2, 4, 6}

Total of even number = 3

Total numbers = 6


Pr(even\text{ number\rparen = }(3)/(6)

Pr(rolling a number less than 4) = numbers less than 4/total numbers

numbers less than 4 = {1, 2, 3}

Total of the numbers less than 4 = 3

Total = 6


Pr(less\text{ than 4\rparen = }(3)/(6)

From both numbers listed, we find that 2 is common in both probabilities. We will deduct the intersection

Pr(of the common number) = 1/6


\begin{gathered} Pr(even\text{ number or less number than 4\rparen = Pr\lparen even number\rparen + Pr\lparen less than 4\rparen - Pr\lparen common number\rparen} \\ \\ Pr(even\text{ number or less number than 4\rparen= }(3)/(6)\text{ + }(3)/(6)-(1)/(6) \\ \\ Pr(even\text{ number or less number than 4\rparen= }(3+3-1)/(6) \\ \\ Pr(even\text{ number or less number than 4\rparen= 5/6} \end{gathered}

User Kiamoz
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