Question

This question was asked in UPSC . Pls answer. give it a try 5 - 4 = 23.
8 - 1 = 63.
6 -16 = 32
9 - 9 = 78
3 - 9 = 6
3 - 81 = ?
Explain the logic. Challenge for all masterminds!!

Answer 1

Given:

5 - 4 = 23, 8 - 1 = 63, 6 -16 = 32 , 9 - 9 = 78 , 3 - 9 = 6

We have to find, the value of 3 - 81 = ?

Solution:

The patter follow:

a - b = $a^{2} -\sqrt{b}$

5 - 4 = $5^{2} -\sqrt{4}$

= 25 - 2 = 23

8 - 1 = $8^{2} -\sqrt{1}$

= 64 - 1 = 63

6 - 16 = $6^{2} -\sqrt{16}$

= 36 - 4 = 32

9 - 9 = $9^{2} -\sqrt{9}$

= 81 - 3 = 78

3 - 9 = $3^{2} -\sqrt{9}$

= 9 - 3 = 6

Similarly,

? = 3 - 81 = $3^{2} -\sqrt{81}$

= 9 - 9 = 0

∴ Missing number (?) = 0