Quantitative Aptitude - Arithmetic Ability Questions

End of first year     :  10000 x (3/5) = Rs. 6000
End of second year :  6000 x (3/5) = Rs. 3600
End of third year    :  3600 x (3/5) = Rs. 2160

Let number of pages in a book = p

According to questions

p - [3p/7 + (2/5 x 4p/7)] = 36

= p - 23p/35 = 36

=> 12p = 36 × 35

p = 105

Given A & B in partnership

A Invests 116000 for 12 months 

=> A's share = 116000 x 12 = 13,92,000

B Invests for 6 months

=> B's share = 144000 x 6 = 8,64,000

Their Ratio = 1392 : 864 = 29 : 18

Let the Annual profit = P

Given B's share = Rs. 9000

=> 18/47 x P = 9000

=> P = 9000 x 47/18

=> P = 23,500

Hence, Overall profit = P = Rs. 23,500

Given a secret is told to 3 persons in 3 minutes.
And if the process continues with each person saying 3 other persons,
In 30 minutes => the rocess for 10 times because each person time is 3 minutes.
Required number of persons = 3 + 32 + 33 + .... + 39 + 310

Now it forms a geometric progression,

Sum to n terms is S = arn - 1r - 1

Here a = 3, r = 3

 
=> 59048 x 3 /2

= 88572.

Let N be the required number. 

=> 60100x27x34xN=2664  

=> N = 2664x2x7x5/9  

=> N = 20720.

Given,
S.I = 3 Principal Amount
=> 3A = A x 16 x R/100
By solving, we get
=> R = 18.75%

S = { 1, 2, 3, 4, 5, 6 } 

=> n(S) = 6

E = { 3, 6}

=> n(E) = 2

Therefore, P(E) = 2/6 =1/3