Exams

F-F = 4 - 4 = 0

Ca-F = 4 - 1 = 3.0

H-F = 4 - 2.2 = 1.8

Na-F = 4 - 0.93 = 3.07

Hence, the highest electronegativity difference is in Na-F.

The given series follows the pattern that,

18, 97, 26, 91, ?, 83

=> 18 + 8 = 26

=> 97 - 8 = 91

=> 26 + 8 = 34

=> 91 - 8 = 83

Hence, the missing number is 34.

Hydrogen Bomb is based on the principle of Nuclear Fusion.

• Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.

• The difference in mass between the reactants and products is manifested as either the release or absorption of energy.

Given Number:     4  2  1  5  7  9  3  6  8

Ascending order:  1  2  3  4  5  6  7  8  9

Hence the required pairs are  12, 49, 16

Let the sum be Rs.P.then
P(1+R/100)^3=6690…(i) and P(1+R/100)^6=10035…(ii)
On dividing,we get (1+R/100)^3=10025/6690=3/2.
Substituting this value in (i),we get:
P*(3/2)=6690 or P=(6690*2/3)=4460
Hence,the sum is rs.4460.

Given series follows Cubes on Prime Numbers 

i.e 23, 33, 53,...but  93is 1331

so 1381 is wrong