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Number series (next term): Increasing differences by a constant step of 5. Given sequence: 6, 11, 21, 36, 56, ? Identify the missing number that continues the pattern. Choose the correct value.

Difficulty: Easy

Correct Answer: 81

Explanation:

Given data
Sequence: 6, 11, 21, 36, 56, ?

Concept/Approach
Look at first differences; if those grow with a fixed increment, extend the pattern.

Step-by-step calculation
11 − 6 = 521 − 11 = 1036 − 21 = 1556 − 36 = 20Next difference = 25 (adds +5 each time)Missing term = 56 + 25 = 81

Verification/Alternative
Differences: 5, 10, 15, 20, 25 → arithmetic progression with d = 5.

Common pitfalls
Confusing with multiplication; it is a simple second-order linear pattern.

Final Answer
81

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