Welcome to the third of our Medium level Eleven Plus maths quizzes on Number Sequences. In the first two we introduced you to the nth term and asked you to create a sequence of numbers from it. In this one we turn the tables. We shall give you a sequence of numbers and ask you to find the rule for the nth term which created it.
These can be a bit tricky. It might be obvious that the numbers are going up by 4 each time, but the rule won’t be “n + 4”. That rule would give you the following sequence:
5, 6, 7, 8, … (1 + 4 = 5, 2 + 4 = 6, 3 + 4 = 7, 4 + 4 = 8, etc.)
The best advice I can give you is to look at the four options you are presented with, and to try them out. Only one of the answers will work for all the numbers in the sequence. It’s your job to find out which!