When you toss a coin, it could land on heads or tails. These
are the only two possible outcomes.

The probability of falling on heads is 1 chance in 2 possibilities.

Mathematicians write this as P(heads) = 1/2 or 0.5

Dice roll

A dice has six sides. They are numbered 1, 2, 3, 4, 5, 6.

What is the probability of
throwing a six?

What is the probability of
throwing an EVEN number?

Brilliant! There are THREE even numbers (2, 4 and 6). So the
probability is 3 in 6. You could write P(even) = 3/6. If you know
your fractions, this is the same as 1/2.