Quantitative Reasoning · Hard
Hard number series puzzles
16 hard puzzles. Which number comes next? Each one links to its answer and a worked solution.
About this set
Hard series add the two previous numbers, double and add a constant, double the gaps, or alternate two operations. Rules in these 16 puzzles: sum of the previous two (6 of 16), double plus a constant (5 of 16), doubling gaps (3 of 16), alternating steps (2 of 16).
Want your own number? The test is 25 visual puzzles, about 12 minutes, no sign-up.
- Plate 01 · Number Seriesdouble plus a constant
7, 15, 31, 63, 127, ?
- Plate 02 · Number Seriesdoubling gaps
7, 11, 19, 35, 67, ?
- Plate 03 · Number Seriessum of the previous two
1, 1, 2, 3, 5, 8, ?
- Plate 04 · Number Seriessum of the previous two
3, 3, 6, 9, 15, 24, ?
- Plate 05 · Number Seriessum of the previous two
3, 6, 9, 15, 24, ?
- Plate 06 · Number Seriesdoubling gaps
3, 4, 6, 10, 18, ?
- Plate 07 · Number Seriesdoubling gaps
2, 3, 5, 9, 17, ?
- Plate 08 · Number Seriesdouble plus a constant
5, 13, 29, 61, 125, ?
- Plate 09 · Number Seriesdouble plus a constant
4, 6, 10, 18, 34, ?
- Plate 10 · Number Seriessum of the previous two
1, 7, 8, 15, 23, ?
- Plate 11 · Number Seriessum of the previous two
1, 5, 6, 11, 17, ?
- Plate 12 · Number Seriessum of the previous two
1, 6, 7, 13, 20, ?
- Plate 13 · Number Seriesdouble plus a constant
5, 11, 23, 47, 95, 191, ?
- Plate 14 · Number Seriesdouble plus a constant
2, 7, 17, 37, 77, 157, ?
- Plate 15 · Number Seriesalternating steps
2, 6, 12, 16, 32, ?
- Plate 16 · Number Seriesalternating steps
3, 6, 10, 20, 24, ?
Rules in this set
| Rule | Puzzles |
|---|---|
| sum of the previous two | 6 |
| double plus a constant | 5 |
| doubling gaps | 3 |
| alternating steps | 2 |
Other levels: easy number series puzzles · medium number series puzzles · all number series puzzles · how to solve them
2 questions
Questions
How hard are the hard number series puzzles?
Hard series add the two previous numbers, double and add a constant, double the gaps, or alternate two operations. The rules used in this set: sum of the previous two (6), double plus a constant (5), doubling gaps (3), alternating steps (2).
Can I see the answers?
Yes. Every puzzle page has a Show the answer button with the correct option and a step-by-step solution. You can also tap an option first to check yourself.
Related
- No. 01Number Series puzzles50 puzzles, easy to hard. Which number comes next?
- No. 02Easy number series17 easy puzzles with answers and worked solutions.
- No. 03Medium number series17 medium puzzles with answers and worked solutions.
- No. 04Number Series #1 (hard)Which number comes next? Hard, with the answer explained.
- No. 05Number sequence testTen number series, 30 seconds each. Find the rule.
25 puzzles · about 12 min
Find your IQ in 12 minutes.
25 visual puzzles, free to take. Your full result, with your estimated IQ, percentile and five-area breakdown, is $4.95 one time.
Free to take. Full result $4.95, one time. No subscription.