alleryGaps of 5, 10, 15, 20 build 6, 11, 21, 36, 56. Which number is next?
A76
B86
C81
D80
Answer & Solution
Correct answer: C. 81
The gaps are 5, 10, 15, 20, so the next gap is 25 and 56 + 25 = 81.
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