There are ten cards total, and eight cards that are not threes. This makes the probability of drawing a three

First, add the total number of marbles, which is．There are 18 red marbles, so you set up a fraction．

If you simplify by dividing the numerator and denominator by 2, you get．

Probability = total number of possible outcomes/sample space.

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To find the probability of an outcome, set up a fraction:

Since there are 12 blue cars (part) out of 68 cars in all (total possible) the fraction looks like this:

If you reduce the fraction by 4 (because the numerator and the denominator are both divisible by 4 which makes 4 the GCF (greatest common factor), it becomes:

There aregreen marbles andred marbles in the bag. Adding these amounts together givesmarbles in the bag that are not red. If allof these were drawn before any red marble, this would requiredraws atmarbles per draw (). Therefore, it is possible to draw up totimes without drawing a red marble.

To find the probability of picking a sugar cookie from the bag of cookies, we need to set up a fraction like this:

The problem tells us that Mikey has 4 sugar cookies, so we can put that on the top of the fraction. The total number of cookies is equal to 6 chocolate chip cookies + 4 sugar cookies + 2 oatmeal raisin cookies, giving us a sum of 12 (which goes on the bottom of the fraction). That gives Mikey achance of picking a sugar cookie!

To find the probability of picking a mushroom slice from the pizza pie, we should set up a fraction like this:

The problem tells us that we have 3 mushroom slices, so we can put that on the top of the fraction. The problem also tells us that we have 8 total slices in the pizza pie, so that can go on the bottom of the fraction. That gives Sofia achance of picking a mushroom slice!

The number of total possible arrangements of three items in a row is, or．

We can write out all the possible arrangments and count the number in which Sarah sits in the middle.

1)

2)

3)

4)

5)

6)

Inout ofpossible arrangements, Sarah sits in the middle. Expressed as a fraction, this is, which is equivalent to．

To find the probability of picking a pink shirt from the box, we need to set up a fraction:．这个问题告诉我们,香农有4个粉红色史rts, so we can put that on the top of the fraction. The total number of shirts is 9, which goes on the bottom of the fraction. That gives Shannon a机会选择粉红色的衬衫从盒子里!

To find the probability of Tucker catching a tuna or a trout, we need to set up a fraction like this:．The problem tells us that there are 5 tuna and 3 trout in the pond, so we can put 8 on the top of the fraction. The total number of fish in the pond is 15, so that goes on the bottom of the fraction. That gives Tucker an8/15chance of catching a tuna or trout!