Number Sequences

These sequences can be great fun if you treat them as a game.  Here you have to guess the rule using the clues that you have been given.

These type of questions give you some numbers and you have to find the missing numbers.

Here is an easy example

Fill in the missing numbers and find the rule

2       4          6          _          10           12          14          _

The answer is easy its 8 and 16, the sequence is growing by two each time. So the rule is add 2 to the last number to find the next.

Here is another way to solve this kind of problem Here we look at the differences between the numbers.  Start at the second number and take away the number before it. Here we see the difference of 2 between every number.

Many patterns can be found by finding the difference and this helps us to predict what will come next

Try find the difference in the following sequence  You see the differences here help you to find the underlying pattern.

This can be great fun because you can make the rules you use to find the next number in the sequence harder and harder.

Try these below and see if you can find the solution to these puzzles

 1.       200      175      150     _       100      _          _ Answer 2.      1       2       4     8     16     _       64     _ Answer 3.      6000      3000       _       750   325 Answer 4.      1       1       2       3       5       _       13     21 Answer

Well how did you find these? We will come back to these at a later date. Well done!

 200   175   150   125_ 100   50     25 Return to questions Subtract 25

 1       2       4       16     32     64     128 Return to questions Double the next number.

 1     1     2         3       5       8       13     21 Finished Add the last two numbers together to get the next one