Study Guide & Educational Overview
### How to Crack Any Number Series Problem
When faced with an unknown numerical sequence, systematically test these four pattern types:
1. **First & Second Differences:** Subtract each number from its successor. If the first differences are not constant, examine the *differences between differences* (e.g. +4, +6, +8 indicates a quadratic $n^2$ pattern).
2. **Special Integer Sequences:** Always check for prime numbers (2, 3, 5, 7, 11, 13, 17, 19, 23), square numbers ($n^2$), and cubic numbers ($n^3$).
3. **Fibonacci / Additive Sequences:** Check if each term is formed by adding the previous two or three terms ($T_n = T_{n-1} + T_{n-2}$).
4. **Interleaved / Dual Operations:** Some sequences interleave two separate sub-sequences or alternate operations (e.g. $\times 2$, then $-5$).
When faced with an unknown numerical sequence, systematically test these four pattern types:
1. **First & Second Differences:** Subtract each number from its successor. If the first differences are not constant, examine the *differences between differences* (e.g. +4, +6, +8 indicates a quadratic $n^2$ pattern).
2. **Special Integer Sequences:** Always check for prime numbers (2, 3, 5, 7, 11, 13, 17, 19, 23), square numbers ($n^2$), and cubic numbers ($n^3$).
3. **Fibonacci / Additive Sequences:** Check if each term is formed by adding the previous two or three terms ($T_n = T_{n-1} + T_{n-2}$).
4. **Interleaved / Dual Operations:** Some sequences interleave two separate sub-sequences or alternate operations (e.g. $\times 2$, then $-5$).
Frequently Asked Questions
Yes, number sequences are a standard benchmark for measuring fluid intelligence and inductive reasoning in psychometric tests.
Yes, click the Hint button on any question to view a progressive clue without giving away the final number.