Objective: Recognise the place value of each digit in a four-digit number

Investigation sheet (print-out)

Using the digits 1, 1, 2, 2 you can make the following four-digit numbers:

1122,

1212,

1221,

2211,

2121,

2112.

Predict how many different numbers you can make using the digits 1, 1, 2, 3 then find all of the possibilities.

How many more numbers can you create using the digits 1, 2, 3, 4? Would this number of possibilities change if you changed the digits to 4, 5, 6, 7 for

example?

Answers:

Using 1, 1, 2, 3

1123, 1132, 1213, 1312, 1231, 1321, 2113, 2131, 2311, 3211, 3121, 3112.

There are a total of 12 possible answers (unless I have missed any!).

Using 1, 2, 3, 4

1234, 1243, 1324, 1342, 1423, 1432, 2134, 2143, 2314, 2341, 2413, 2431, 3124, 3142, 3214, 3241, 3412, 3421, 4123, 4132, 4213, 4231, 4312, 4321.

There are a total of 24 possible answers.