1, 1, 2, 3, 5, 8, 13, 21, 34, ?



The answer is 55.

Each new number in the sequence is the sum of the two previous numbers. Children often find this a difficult one to solve because the usual methods they are commonly taught to spot patterns in sequences don’t work – try looking at the differences between each term and you’ll see why.

Look at the ratios between each term (divide the second term by the first, the third by the second, etc.) and you will see more of a pattern emerging – the number you are closing in on is known as the Golden Ratio, 1.618… If you’d like to find out more about Fibonacci numbers, their properties and their connections to nature, visit this great site here!