Number Series Explanation 3 - Alternating Pattern

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Example 3

Alternating_Example_3_1.png

This is a difficult example. It is immediately clear that there cannot be a monotonous or exponential relationship, because the numbers are not continuously increasing or decreasing. Check if the same transformation is applied between number 1 and number 2 as between number 3 and number 4 or number 4 and number 5. The transformation is *2 every other step.

The other pattern is more difficult to find. Since the step from -18 to -15 will in principle not be a multiplication, it is clear that the additional arches must be drawn.

Alternating_Example_3_2.png

The second series does not always have the same transformation. First + 3, then +6, then +9. So the answer is -39.


Tip
: If a question contains more than 5 numbers, the chances of one of the more difficult patterns are higher. You don't have to look for these kinds of difficult patterns if only 4 numbers are given.

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