How to Solve Probability Problems

How to Solve Probability Problems

 Read,3 minutes

The Solution for Probability Problems

It is possible to solve a lot of easy probability problems merely by understanding 2 basic rules, which are:

  • The possibility of any sample point could be in a range of 0 to 1.
  • The total probabilities of all the sample points within a sample space equals 1.

Probability of Sample Points

The possibility of a sample point happening is a measure of the possibility sample point will happen.

Example One

Why don’t we do a basic statistical experiment? We’ll flip a coin once. This coin flip could have 1 or 2 equally-possible outcomes – tails or heads. Together, those results represent the sample space of this experiment. Independently, each of the outcomes stands for a sample point within the sample space. What’s the chances for each sample point?

Solution:

The total of the chances for every sample point has to be 1. Plus the chances of acquiring a head is the same as the chances of getting a tail. So, the chances for each sample point (tails or heads) has to be 12.

Chances for an Event

The chance for an event is a measure of the possibility it will happen. By agreement, statisticians have formed these rules.

  • The chances for an event can be in the range of zero to 1.
  • The chances of event A is the total of the chances of all the sample points for event A.
  • The chance of event A is shown via P(A).

So, if event A weren’t likely to happen, then P(A) is going to be close to zero. So if event A were quite likely to happen, P(A) would be near 1.

Example two

Let’s pull a card from a deck of poker cards. What’s the chances we’ll get a spade?

Solution:

The sample space for this experiment comprises fifty-two cards, so the chances for each sample point is 152 . Because there are thirteen spades in a deck, the chances of pulling out a spade is:
P(Spade) = 13×152 = 14

Conclusion

  • Probability is the chance of a future event. It’s shown as a number in-between zero (could not ever happen) to 1 (this is going to happen all the time).
  • Probability can be shown using fractions, decimals, or percentages.
  • To find a solution to a probability problem ascertain the event, and figure out the amount of outcomes for the event, you should utilize probability law: number of favorableoutcomestotal number of possible outcomes 

Free printable Worksheets

Exercises for Probability Problems

1) A number is chosen at random from 1 to 23. Find the probability of selecting a 2 or smaller.

2) A number is chosen at random from 1 to 16. Find the probability of selecting prime numbers.

3) A number is chosen at random from 1 to 46. Find the probability of selecting prime numbers.

4) Bag A contains 9 red marbles and 5 green marbles. Bag B contains 3 black marbles and 8 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B?

5) Bag A contains 23 red marbles and 5 green marbles. Bag B contains 1 black marbles and 9 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B?

6) Bag A contains 16 red marbles and 7 green marbles. Bag B contains 8 black marbles and 2 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B?

7) Bag A contains 17 red marbles and 9 green marbles. Bag B contains 7 black marbles and 6 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B?

8) Bag A contains 24 red marbles and 7 green marbles. Bag B contains 5 black marbles and 9 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B?

9) A number is chosen at random from 1 to 32. Find the probability of selecting prime numbers.

10) A number is chosen at random from 1 to 18. Find the probability of selecting prime numbers.

 
1) A number is chosen at random from 1 to 23. Find the probability of selecting a 2 or smaller.  223
2) A number is chosen at random from 1 to 16. Find the probability of selecting prime numbers.  38
3) A number is chosen at random from 1 to 46. Find the probability of selecting prime numbers.  723
4) Bag A contains 9 red marbles and 5 green marbles. Bag B contains 3 black marbles and 8 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B? 514 ,311
5) Bag A contains 23 red marbles and 5 green marbles. Bag B contains 1 black marbles and 9 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B? 528 ,110
6) Bag A contains 16 red marbles and 7 green marbles. Bag B contains 8 black marbles and 2 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B? 723 ,45
7) Bag A contains 17 red marbles and 9 green marbles. Bag B contains 7 black marbles and 6 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B? 926 ,713
8) Bag A contains 24 red marbles and 7 green marbles. Bag B contains 5 black marbles and 9 orange marbles. What is the probability of selecting a green marble at random from bag A? What is the probability of selecting a black marble at random from Bag B? 731 ,514
9) A number is chosen at random from 1 to 32. Find the probability of selecting prime numbers.  1132
10) A number is chosen at random from 1 to 18. Find the probability of selecting prime numbers.  718

Probability Problems Quiz