Aptitude and Reasoning Questions

let ratio be x.

Hence no. of coins be 5x ,9x , 4x respectively

Now given total amount = Rs.206

=> (.50)(5x) + (.25)(9x) + (.10)(4x) = 206

we get x = 40

=> No. of 50p coins = 200

=> No. of 25p coins = 360

=> No. of 10p coins = 160

4th to the right of 20th letter from the right means (20 - 4 =) 16th from the right.

16th letter from the right = (26 - 16 + 1 =) 11th from the left, i.e K

First letters are common. Second letters are:b, c, c, c, c. One of the four words having c is the last word. Let us see the third letters now ,there are: t, c, q, h. Clearly t is the last. Hence Actuate is the last word. 

Fiest series : 3, 5, 7, 9

Second series : 5, 19, 41, ?

 Difference of Second series are 14, 22, 30 etc

Next term is 41+30 i.e equal to 71

Each of the numbers except 81 is a prime number.

Numbers are (2³ - 1), (3³ - 1), (4³ - 1), (5³ - 1), (6³ - 1), (7³ - 1) etc.

So, the next number is (8³ - 1) = (512 - 1) = 511.

The differences between two successive terms from the beginning are 7, 5, 7, 5, 7, 5.

So, 40 is wrong.

Let A, B, C be the respective events of solving the problem and A , B, C be the respective events of not solving the problem. Then A, B, C are independent event

∴A, B, C are independent events

Now,  P(A) = 1/2 , P(B) = 1/3 and P(C)=1/4

 PA=12, PB=23, PC= 34

∴ P( none  solves the problem) = P(not A) and (not B) and (not C)  

                  = PA∩B∩C 

                  = PAPBPC         ∵ A, B, C are Independent                       

                  =  12×23×34  

                  = 14  

Hence, P(the problem will be solved) = 1 - P(none solves the problem) 

                = 1-14= 3/4