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Weekly Problem 38 - 2009

Stage: 3 Short Challenge Level: Challenge Level:1

The first two terms of a sequence are $\frac{2}{3}$ and $\frac{4}{5}$. Each term after the second 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.

View the previous week's solution