Question

In a single throw of a die, what is the probability of attaining a number of 4 or lower?

Answer 1

How many possibilities are there? 6

How likely are you to get any number? They're all equally likely. So each number has a one out of six chance of getting picked. We write that as 1/6 for any one you pick.

So what's the probability of rolling either 1 or 2? Well, you have a 1/6 chance of getting a 1 and a 1/6 chance of getting a 2. So you add them up and get \[\frac{1}{6}+\frac{1}{6}=\frac{2}{6}=\frac{1}{3}\]

Now back to your question, what is the probability of 4 or lower? Well, just add up the individual probabilities of getting each one.

Answer 2

How can you get 4 or less? Well, you can get 1 or 2 or 3 or 4.
Anytime you can answer the probability qestion with “or” you add the individual probabilities:
P(4 or less) = P(1) + P(2) + P(3) + P(4)
Each of these events is equally likely, so
P(4 or less) = 1/6 + 1/6 + 1/6 + 1/6 = 4/6 = 2/3

Answer 3

0.67

Answer 4

?

Answer 5

2/3 is approximately .67