Probability • Sample space

Two bags, three probabilities

Choose one digit from each bag. Bag 1 gives the tens digit; Bag 2 gives the ones digit. Every pair is equally likely.

BAG 1 · TENS
135
BAG 2 · ONES
2468
3 × 4 = 12equally likely two-digit outcomes

Explore first

The complete sample space

Rows show the tens digit; columns show the ones digit. Select an event to highlight its favourable outcomes.

Numbers divisible by 3 are highlighted
Tens ↓ / Ones →2468
favourable outcome 4 of 12

For divisibility by 3, add the digits. A number is divisible by 3 when its digit sum is a multiple of 3.

Your turn

Find each probability

0 of 3 checked

Enter a fraction. Use the total number of equally likely outcomes as the denominator, then give your answer in simplest form.

a

Divisible by 3

What is the probability that the number formed is divisible by 3?

b

A multiple of 4

What is the probability that the number formed is a multiple of 4?

c

An odd number

What is the probability that the number formed is odd?