Explanation

To find the missing term in the sequence, let's examine the pattern:

1/3, 1/8, ?, 2/3

First, notice the denominators: 3, 8, ?, 3.

The denominators don't seem to follow a straightforward arithmetic or geometric progression. Let's look at the numerators:

1, 1, ?, 2

The numerators seem to increase by 1 each time.

If we consider that the numerators increase by 1 and the denominators are not following a clear pattern, we could assume a pattern where the numerators increase by 1 every two terms.

Following this pattern, the missing term should have a numerator of 1, and since it's the second term after 1/8, the denominator should be 5 (since 3 + 2 = 5).

So, the missing term is 1/5.

Therefore, the completed series is:

1/3, 1/8, 1/5, 2/3