Question

you roll a number cube numbered from 1 to 6. What is the probability of rolling a composite number? p (composite number) = ?

Answer 1

Composite numbers are numbers that have more than two factors aside from 1 and itself.

Let's determine the factors of numbers 1 - 6.

1: 1 x 1 → one factor only (1)

2: 2 x 1 → two factors only (1 and itself)

3: 3 x 1 → two factors only (1 and itself)

4: 4 x 1 ad 2 x 2 → three factors (1, 2, and itself)

5: 5 x 1 f→ two factors onl y(1 and itself

6: 6 x 1 and 3 x 2 )→ four factors (1, 2, 3, and itself).

As we can see above, only 4 and 6 are composite numbers. Hence, out of 6 numbers in a cube, only 2 of them are composite.

Therefore, the probability of rolling a composite number is 2 over 6 or 1 over 3.

`P(composite\text{ }number)=(2)/(6)or(1)/(3)`

Answer: The probability of rolling a composite number is 1/3.