Work on Solving Number Series
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Number Series |
Number series, which are given on most intelligence tests and which you will find in a good paperback puzzle book. They focus your scan tightly, thereby making your search a little easier and helping you to define and hone the process.
The difference with number series and insight in general is that with number you must take extra trouble to 'lock in' on a find, then proceed to check its accuracy. If your answer comes up incorrect, you 'lock in' on another find, over and over until you find the one that really works, the one that satisfies the requirements of the series. By doing this repeatedly, you will learn to can much more efficiently. Here's an example of a number series:
Exercise : 4 9 25 49 81 (?) - (Find last number)
The correct answer is 121, that i s 11 x 11. And here is how to arrive at that solution.
The first successful step you take in your scanning process, your first insight into solving the problem is noticing that the above numbers are all squares: 4 is 2 x 2; 9 is 3 x 3; 25 is 5 x 5 ; 49 is 7 x 7; 81 is 9 x 9. therefore the square root number series would read:
2 3 5 7 9 (?)
Scan that series, and your second insight will be that the above are all prime numbers, numbers which can be evenly divided only by themselves and by 1. Logically, then the next number in that series would have to be the sixth prime number, 11. Going back to the original series. the answer would be 11 squared, or 121.
The following number series problems will offer you some practice. Now you know that your first step. your first insight is to determine what the given numbers have in common so that you can extrapolate that similarity to discover the unknown number.
Exercise 1 : 2 9 28 65 126 (?) - (Find last number)
Exercise 2 : 5 25 61 113 181 (?) - (Find last number)
Exercise 3 : 7 22 52 102 178 (?) - (Find last number)
Answers:
Exercise 1 : 271
Exercise 2 : 265
Exercise 3 : 286