Bank Clerk Questions

Here, S = {1, 2, 3, 4, ...., 19, 20}=> n(s) = 20
Let E = event of getting a multiple of 4 or 15
=multiples od 4 are {4, 8, 12, 16, 20}
And multiples of 15 means multiples of 3 and 5
= {3, 6 , 9, 12, 15, 18, 5, 10, 15, 20}.
= the common multiple is only (15).
=> E = n(E)= 6
Required Probability = P(E) = n(E)/n(S) = 6/20 = 3/10.

Physiology is a branch of biology. Similarly, mathematics is a branch of philosophy.

Hence, Physiology : Biology :: Metaphysics : Philosophy.

Given that, a woman has seven children. Half of them are boys. 

Half of 7 is 3.5 which is not possible. And it is possible in only one way that all the children must be boys. Then half of them are boys.

Let the present age of Pinky be x years

Then the age of Mary is x - 12 years

After 3 years,

Ratio of  MaryPinky = x - 9x + 3 = 58

8x - 72 = 5x +15

=> 3x = 87

=> x = 29

=> Age of Pinky = 29 years

=> Age of Mary = 29 - 12 = 17 years

Present age of Sam = 29 + 17 = 46

Before 15 years Sam age = 46 - 15 = 31 years.

Since Akhil has no brother or sister, so he is his father's only son.
So wife of Akhil's father's son---Akhil's wife.
Thus, Akhil's wife is the man's mother or the man is Akhil's son.

Profit would be maximum if watches are brought for Rs. 200 and sold for Rs. 425
Profit = Rs. (425 - 200) = Rs. 225
Profit of 9 watches = Rs. 225 x 9 = Rs.2,025.