Hello!
Let's start with some probability basics.
Probability = Number of desired outcomes/Total number of possible outcomes
Because of this, probability is always between 0 and 1
The total number of possible outcome in rolling dice is 36
That is because there are 6 possible outcomes in the first die, and six possible outcomes for the second die.
Therefore there are 6 x 6 = 36 total possible outcomes
If we were to ask what is the probability of getting a picture of a cat on both dice, the probability is 0 because there are 0 outcomes that will feature a cat, unfortunately, out of the 36 possible outcomes
\(\frac{0}{36}\) = 0
If we were to ask what is the probability of getting a number from a roll of dice, that probability is 1 because there are 36 different ways to get a number out of the 36 possible outcomes of rolling dice. That is to say, all of the possible outcomes will result in a number. The probability is 1 meaning it is 100% a sure thing
\(\frac{36}{36}\) = 1
This question asks what the probability is of the sum of the dice being 5 or higher
Now if we start to think of the possible combinations
1 2
2 3
4 2
4 1
5 1
6 3
3 5
We can see that many add up to 5 or larger, so it is more useful to see how many rolls add up to less than 5 and subtract that number from the total number of rolls
Let's see:
1 1
1 2
1 3
2 1
2 2
3 1
There are 6 different rolls that will add up to less than 5
This is out of 36 total possible rolls
36 - 6 = 30 of the possible rolls will add up to 5 or larger
\(\frac{30}{36 } \)= \(\frac{5}{6}
\)
The answer is (D)
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