Select the number from among the given options that can replace the question mark (?) in the following series.
125, 150, 177, 207, 242, ?
Correct Answer :
284
Solution :
The correct answer is 284.
Let us analyze the pattern in the given number series:
125, 150, 177, 207, 242, ?
We can find the differences between consecutive terms in the series:
First difference:
150 - 125 = 25
177 - 150 = 27
207 - 177 = 30
242 - 207 = 35
Now, let us examine the pattern in the differences obtained: 25, 27, 30, 35. We find the differences of these differences (second-level differences):
27 - 25 = 2
30 - 27 = 3
35 - 30 = 5
The second-level differences are 2, 3, 5, which are consecutive prime numbers.
Following this prime number pattern, the next difference in the second level should be the next prime number, which is 7.
Therefore, the next difference in the first-level differences will be:
35 + 7 = 42
Adding this difference to the last term of the series (242) gives the missing number:
242 + 42 = 284
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