Nowadays the calculator is very familiar to many of us. What did people do to save time working out more difficult problems before the calculator existed?
"Ip dip sky blue! Who's 'it'? It's you!" Where would you position yourself so that you are 'it' if there are two players? Three players ...?
This problem challenges you to find out how many odd numbers there are between pairs of numbers. Can you find a pair of numbers that has four odds between them?
In this problem it is not the squares that jump, you do the jumping! It is not a race, but a game of skill. You have to be able to look ahead. The idea is to go round the track in as few jumps as possible, keeping to the rules.
The first line of the track looks like this:
You start on the green square which tells you that you can jump forward either one or three squares. Here is the whole track:
You make your way round the track and finish on the red square with 'end' on it.
If you land on a square which has 2 and 3 on it, you can jump forward - or back - either 2 or 3 squares.
If the square has 2 and 0 on it, you can jump forward - or back - only 2 squares.
If the square has 0 and 0 on it, you cannot jump at all. You have to go right back to the beginning and start again!
You can download a larger version here.
You can do this on your own or with a friend.
You can count your jumps by making a note on paper whenever you jump or by counting out twenty counters and taking one from the pile every move.
What is the least number of jumps you can make to get round the whole track?
Which squares do you need to land on?