Odds and Threes
A game for 2 people using a pack of cards. Turn over 2 cards and try to make an odd number or a multiple of 3.
This is a game for two, three or four players.
You will need a pack of cards with the Jacks, Queens and Kings removed. (The Ace is worth one.)
Deal out two cards to each player.
You can add, subtract, multiply or divide the two numbers to make a whole number, or just put them together to make a 2-digit number.
You score one point for making an odd number or a number that can be divided by three.
The player who has the most points after five rounds wins the game.
For example: if you drew a 4 and a 6, you could make the following numbers:
46
64
4 + 6 = 10
4 × 6 = 24
6 - 4 = 2
But only 24 would score a point. Can you see why?
Once you've played a few times, have a think about these questions:
Can you tell as soon as you get your cards whether or not you will be able to make an odd number?
Is there a quick way to tell if a number is divisible by 3?
How could you change the game to make it more challenging?
Printable NRICH Roadshow resource.