Exams

Let the total population be 'P'

P x (96/100) = 23040

P = 240 * 100

P = 24000.

 H   L   C   N    T    A   U   I   O

      L        N          A        I

There are total 131 letters out of which 7 are consonants and 6 are vowels. Also ther are 2L's , 2N's, 2A's and 2I's.

If all the consonants  are together then the numberof arrangements = 7!2!x 1/2! .

But the 7 consonants  can be arranged themselves in  7!2! x 1/2! ways. 

Hence the required number of ways = 7!2!2!2 = 1587600

The Sound Following the flash of lighting is because of Thunder.

Lightning is seen earlier than thunder because light travels much faster than sound.

The roar of thunder is the result of a shock wave produced when lightning super-heats the air through which it passes, causing that air to expand very rapidly. This rapid expansion of air creates a shock wave that travels outward at close to the speed of sound.

Here the second one follows the first one. That is a nurse follows a doctor and similarly, a follower follows a leader.

Hence, Doctor : Nurse :: Leader : Follower.

In 12 hours, they are at right angles 22 times.
In 24 hours, they are at right angles 44 times.