Draw a number line on a piece of paper, marked from 0 to 20, like
this:
(You could print off this sheet which has
several number lines drawn on it.)
This challenge is a game for two players.
The first player chooses two numbers in this grid and either
or
.
He or she then marks the answer to the sum on the number
line.
The second player then chooses two numbers and either
or
, and
marks that number in a different colour on the number line.
If the answer is too big or too small to be marked on the
number line, the player misses a go.
The winner is the player to get four marks in a row with none
of their opponent's marks in between.
What good ways do you have of winning the game?
Does it matter if you go first or second?
[This game is adapted from a
SMILE Centre card. See www.smilemathematics.co.uk
for information about their
mathematics resources.]