What is X in the sequence 4, 196, 16, 144, 36, 100, 64, X?
- A48
- B64Correct
- C125
- D256
Explanation
The given sequence is an alternating series consisting of two separate patterns.
The first pattern involves the numbers at odd positions: 4, 16, 36, and 64. These are the squares of consecutive even numbers: 2 squared is 4, 4 squared is 16, 6 squared is 36, and 8 squared is 64.
The second pattern involves the numbers at even positions: 196, 144, 100, and X. These are the squares of even numbers in descending order: 14 squared is 196, 12 squared is 144, and 10 squared is 100.
Following this descending even number pattern, the next number for X should be the square of 8. Since 8 squared is 64, the value of X is 64.
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