Solve the Number Sequence: 1, 3, 2, 3, 4, 9, x

To determine the value of x in the sequence 1, 3, 2, 3, 4, 9, x, we need to identify the pattern or relationship between the numbers.

Looking at the sequence, we can observe that each number is obtained by adding the previous two numbers. For example:

• 3 is obtained by adding 1 and 2.
• 2 is obtained by adding 3 and 1.
• 3 is obtained by adding 2 and 3.
• 4 is obtained by adding 3 and 2.
• 9 is obtained by adding 4 and 3.

Following this pattern, the next number should be obtained by adding the last two numbers in the sequence. Therefore, x should be obtained by adding 4 and 9, which equals 13.

Therefore, the correct answer is x = 13.