In a certain test there are n questions. In this test 2n−i students gave wrong answers to at least i questions, where i = 1, 2, 3, ......, n. If the total number of wrong answers given is 2047, then n is equal to
A
13
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
12
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
10
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
11
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution
The correct option is D 11 The total number of wrong answers =n.20+(n−1)21+(n−2)22+....+12n−1=2047