Basic Probability For Young Students

Hi there. This math post for kids is on basic probability. It is assumed that the young student is  familiar with fractions.

Topics

• The Meaning Of Probability
  
• Examples With Coins, Dice and Marbles
• Practice Problems
• Answers To Practice Problems

The Meaning Of Probability

Probability is a number from 0 to 1 (with 0 and 1 included) which indicates the likelihood of something happening. Probabilities can be opinion-based (subjective) or it can be more objective/theoretical with using known facts. Here, we use probabilities based on facts on coins, dice and choosing marbles.

An example of an objective probability would be the probability of flipping a heads on a fair coin is 50%. One example of a opinion-based probability would be estimating the chance of rain for tomorrow. The chance of rain is an estimate or a guess.

A probability of 0 means that the chance of something happening is impossible. On the other end, a probability of 1 or 100% means that the chance of something happening is certain. A probability of 0.5 or 50% represents equally likely, a number between 0 and 0.5 indicates not likely, and probabilities between 0.5 and 1 would be usually likely.

Pixabay Image Source; Probability Scale

Examples With Coins, Dice and Marbles

This section will provide a basic overview of probabilities with a fair coin, a fair die and with drawing one marble.

Many probabilities are expressed in terms of fractions. The bottom number or denominator of the fraction represents the number of possible choices. The numerator or top number in the fraction  represents the number of choices from a desired group. This will make more sense in the examples (screenshot from my R Markdown script).

Pixabay Image: Marbles

Practice Problems

1) What is the probability of flipping a tails on a fair coin?

2) What is the probability of rolling a 5 on a die?

3) What is the probability of rolling an even number on a die? What about an odd number?

4) On a standard six-sided die, what is the probability of rolling a number lower than 5?

5) What is the probability of rolling a number that is not a 6 on a standard six-sided die?

For questions 6), 7) and 8)

You have 10 marbles in a bag. Five of them are red, two are green and the rest are blue. You randomly select one marble from the bag. 

6) What is the probability that the marble you pick is green?

7) What is the probability that the marble you pick is red?

8) What is the chance that the picked marble is blue?

Answers To Practice Problems

Pixabay Image: Coin

Thank you for reading.