Which of the following numbers will replace the question mark (?) in the given series?
1.6, 2.5, 3.6,  ?,  6.4, 8.1

Given: 1.6, 2.5, 3.6,  ?,  6.4, 8.1​

Logic: The pattern follows +0.9, +1.1, +1.3, +1.5, +1.7, increasing by 0.2 each step.
Find the Differences
2.5 - 1.6 = 0.9
3.6 - 2.5 = 1.1
? - 3.6 = ?
6.4 - ? = ?
8.1 - 6.4 = 1.7
Identify the Pattern in Differences
0.9, 1.1, ?, 1.5, 1.7 (Increasing by 0.2 each step)
The Missing Difference:
1.1 + 0.2 = 1.3
The Missing Number:
? = 3.6 + 1.3 = 4.9
Thus, the Correct option is (c) 4.9
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