What should come in place of the question mark (?) in the given series?

Given series:

66, 77, 99, 132, 176, ?

Step 1: Find the pattern (difference between terms)

• 77 − 66 = 11
• 99 − 77 = 22
• 132 − 99 = 33
• 176 − 132 = 44

👉 Differences are:
11, 22, 33, 44

Step 2: Continue the pattern

Next difference = 55

Step 3: Find the missing number

176 + 55 = 231

Correct Answer:

231

Differences are increasing by +11 each time
👉 11 × 1, 11 × 2, 11 × 3, 11 × 4, 11 × 5

So next = 176 + (11 × 5) = 231