Quantitative Aptitude - Arithmetic Ability Questions

Let the Present age of the son be P, which means he was born P years ago.At the time the son was born, the age of the man was : (48 - P). So, according to the statement made by the man, his age when the son was born should be equal to 2/3 of P.

Therefore, 

Solving, we get P = 28.8 years; which is the present age of the son.

By selling Rs. 100 stock , cash realised = Rs.100-4-14=Rs.3834  

By selling Rs. 2400 stock, cash realised =Rs.3834*1100*2400 = Rs 2298.

As we know we have 10 letter and 10 different address and one more information given that exactly 9 letter will at the correct address....so the remaining one letter automatically reach to their correct address
P(E) = favorable outcomes /total outcomes
Here favorable outcomes are '0'.
So probability is '0'.

ab×bc=45×1516=34=16-916+9

=725

A = P(1 + rt/100)

So, A= 3P (it becomes triples)

3P = P(1 + 8r/100)→r = 25%

Now, when t = 20

⇒A = P(1 + 25*20/100)

⇒A = P(1+ 5)⇒A = 6P

So, it becomes 6 times.

let the side of the square be x meters
length of two sides = 2x meters
diagonal = 2x= 1.414x m

saving on 2x meters = .59x m

saving % = 0.59x2x*100%

= 30% (approx)

16200 = 23×34×52

A perfect cube has a property of having the indices of all its prime factors divisible by 3.

Required number = 32×5 = 9x5 = 45.

Let the number of bricks be 'N'

10 x 4/100 x 6 x 90/100 = 25/100 x 15/100 x 8/100 x N

10 x 4 x 6 x 90 = 15 x 2 x N => N = 720.