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Mean Sequence
Age 11 to 14
ShortChallenge Level 
The first two terms of a sequence are $\frac{2}{3}$ and $\frac{4}{5}$.
Each subsequent term is the mean of the two previous terms.
What is the fifth term in the sequence?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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