10 Random Quantitative Questions [Solutions]

Q.1 ) If n ! has 281 trailing zeros .What is maximum possible value of n.?

Solution : 

This problem is solved by trail n error method using the formula

No of trailing zeros = N/ 5 + N/ 25  +N/125 +……

By solving , we get N = 1132

Q.2) Find the total number of factors , even factors  & odd factors of 928. 

Solution : 

Expressing the given number in “Prime Factorization form ” or  ” Canonical form ” , we get 

928 = 2^ 5  x 29^1

Total number of factors is given by  (5+1)(1+1)  

= 6 x 2

12

 

 Total number of even factors is given by ( 4+1)(1+1)  = 5 x 2 =10

{ Note : Here the power of even base number is reduced by 1 }

Now, total number of odd factors = 12 – 10 = 2

     

 Q.3) Total no of factors that can divide 1728

A).18

B).28

C).24

D).16

 Solution :

 

Expressing the given number in “Prime Factorization form ” or  ” Canonical form ” , we get 

                   1728 =   2^6 x 3^3

  Total  Number of factors = ( 6+1)(3+1) = 7 x 4 = 28

Option B) 28

 

Q.4) The avg age of 8 persons in class is increased by 2 year when two persons aged 35 and 45 year are substituted by 2 different persons ,find average of previous 2 persons age.

 Solution :  

 Assume the avg age of persons before be = n 

Then , we have   there are two people with ages  35 & 45 

                 We have the equation as  (m +35+45)/8 = n

                                  m+80 =8n ————(1)

            From question , the two persons are replaced by other two persons 

    Let the other two persons age be x & y 

       We have  ( m+x+y)/8 = n+2

                ( m+x+y) =  8n + 16 ———–(2)

   Solving two equations , we get  (x+y ) = 48 years

 

 

 

Q.5) Product of three consecutive numbers is 2730 .Find the sum of three numbers. 

A) 39

B) 42

C) 45

D) 29

Solution :   

Consider the numbers as x -1 , x , x+1 

Product : (x^2-1)x = 2730

Sum : 3x =?

(x-1)*x*(x+1)=2730
(x*x*x)-x=2730……………………………(1)
now 39/3=13 ; so the mid term will be 13, put x=13
then 42/3=14 ; put x=14 ; it satisfies eqn(1)
so mid term =14 hence sum =42

   

 

Q.6) Find next term in sequence 8 , 12 ,18 , 27 ,40.5 , ?

Solution : 

Every successive term in sequence is obtained by multiplying the previous term by 1.5 .

Therefore we get , 40.5 x 1.5 = 60.75

 

Q.7) Find odd one out 

 742 , 743 , 633 , 853 , 871 , 990 , 532

Solution :

        First digit = Second digit + third digit

 First term doesn’t satisfy the above condition.

 

Q.8) Find the odd one out. 

  445 , 221 ,109 ,46 ,25 ,11,4

Solution: Solution provided by most of website is somewhat not easy ,

Let me tell you the different method , go on multiplying last term by 2 adding 3 in the above question , we get

4 x 2 + 3 = 11

 11 x 2 +3 = 25 

25 x 2 +3 = 53

And it continues , but 46 is odd one , it did not follow the rule.

Q.9) If Prem scores 2 times the score scored by Praveenkumar  , which of the following scores cannot be total score of two .

A) 23

B) 45

C) 57

D) All above

 

Solution :  

Let the score of Praveenkumar be x , then Prem Score will be 2x 

Total score by both will be x + 2x = 3x

Therefore , the total must be divisible by 3  ,23 is not divisible by 3 .

Option A) 23

Q.10)  If 2 *3 = 17 ; 3 *4 =145 ,   

4 * 2 = 32 , then 5 * 2 =?

Solution :   Logic is  as follows

 2^3 + 3^2 = 17

Similarly , 3 ^4 +4^ 3 = 145 

4^2 +2^ 4 = 32

     5^2 +2^5  = 57

Option C) 57

 

If any error , please do bring to my notice 🙂

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About Praveenkumar P Kalikeri

ABOUT US Hey,Thanks for dropping by .First I would like to Appreciate for your love towards the Mathematics Subject. My name is Praveenkumar Kalikeri. I'm an Engineering Student from Karnataka , India. My Passion for Mathematics , encouraged me to start this blog . I Started loving the Mathematics subject from my schooling days.I was greatly motivated by teachers, parents who always helped me .        Numbers have Beauty !! They fascinated me .. As we all know best method to try out something new is to study old theories , concepts , its drawbacks, etc. I ,myself Started learning Vedic Mathematics at age of 15. Here , I will share vedic maths tricks learned and modified by me in simple manner which will be useful in various competitive exams. "If You Believe , You Can Do".
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