HELP explain 11+ maths question/answer?

[mrsFruitLoops]

Work out the missing term of this number pattern.
2, 2, 3, 4, 6, _ ,14, 22

A) 8
B) 13
C) 9
D) 10

It's 9.
Add the previous 2 numbers together, then subtract 1.

Thank you that's been hurting our heads trying to work it out so we could explain how he can go about getting it right in future.

We have the answer sheet but couldn't work out how they came to that answer.

9- add the two previous numbers together and subtract 1

There’s no one systematic way of dealing with any sequence but looking at the gaps between numbers will often help. If the gap is constant that is an easy linear sequence. In this case you might spot the Fibonacci pattern in the gaps. Doing lots of examples helps to recognise standard patterns.