Verbal Reasoning - Mental Ability Questions

The given series follows,

2

2 x 2 = 4

4 x 3 = 12

12 x 4 = 48

48 x 5 = 240.

Given number is 14278359
As given 1st and 5th digits, 2nd & 6th, 3rd & 7th and 4th & 8th digits are to to be interchanged.
Therfore, the rearranged number is 83591427
Then, the second digit from the right end is 2.

A sponge is a porous material. Rubber is an elastic material. 

Since Rubber is not a Massive or solid and not an inflexible thing, it is elastic. 

Second, fourth and the sixth digits of the number are 3, 1 and 6. Using these digits only once we can make 361, which is a perfect square number. Hence, our answer is 19 x 19 = 361

Letters in the word                     Letters in the alphabet

$$\begin{gathered} PRES \\ - - \end{gathered}$$

                                $$\begin{gathered} PQRS \\ - - \end{gathered}$$

$$\begin{gathered} RESEN \\ - - \end{gathered}$$                             $$\begin{gathered} RQPON \\ - - \end{gathered}$$

The letters move 1, 2, 3, ... steps forward.
The numbers increase by + 3, + 5, + 7, + 9....

Unit digit of this expression is always 1 as the base ends with 1. 

For the tenth place digit we need to multiply the digit in the tenth place of the base and unit digit of the power and take its unit digit.

i.e, tenth place digit in 2151 is 5 and

tenth place digit in power 415 is 1

And the units digit in the product of 5 x 1 = 5

Therefore, last two digits of 2151415 is 51.