OB Question a Day-3

CAT Question a day

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Oliveboard Question of the day

If A = 200
B = A – 99
C = A + B – 98
D = A + B + C – 97 and so on upto Z.

Find the value of 2^-25(Z+1)

Options:

50
51
26
None of these

Solution posted below. Click on the plus sign to view the solution.

Answer and Explanation

Answer key: 2

A = 200

B = 101

C = 203

D = 407

E = 815

This way we see that for the n^th English alphabet (where n>1), the value is (2^n-2 x 100) + (2^n-1 – 1).

So, Z = (2²⁴x100) + (2²⁵-1) So, Z + 1 = (2²⁴x100) + (2²⁵-1) + 1 = 2²⁵(50 + 1)

So, 2^-25(Z+1) = 2^-25 x 2²⁵(50 + 1)

= 51

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6 Comments

Wordpandit on September 2, 2016 at 8:55 am
Guys, thanks for the participation..:)
We have put the solution, in case you need to understand the logic.
Reply
Birinder Kaur on September 1, 2016 at 12:48 pm
51
Reply
karishma on September 1, 2016 at 12:44 pm
51
Reply
Samruddha Khare on September 1, 2016 at 12:23 pm
2^-25=1/2^25=1/33554432
value of z+1=1707081729
1/33554432*1707081729=50.8~51
Reply
Samruddha Khare on September 1, 2016 at 12:16 pm
50.8~ 51
Reply
Sneha Sahu on September 1, 2016 at 10:13 am
51
Reply

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