IBPS PO/Clerk : Numerical Ability/Quantitative Aptitude series-2

Welcome to Coaching Genie's series-2 of Quantitative Aptitude. The Best free IBPS PO Clerk coaching.

11.The average of 40 numbers is 56. If two numbers namely 22 and 63 are discarded, The average of remaining numbers is ?
a)72.1
b)45.3
c)56.7
d)67.3
e)38.6

Ans.
Total of 40 numbers = 40 * 56 = 2240
Average of 38 numbers = 2240 - (22 + 63)/38 = 2155/38 = 56.7 

12.A person knows five different routes from Chennai to Delhi. From Bangalore to mumbai he knows two different routes and from Mumbai to Delhi he knows three different routes. How many routes does he know from Chennai to Delhi?
a)20
b)10
c)50
d)30
e)5

Ans. Total number of routes from Chennai to Delhi = (5 x 2 x 3) = 30.

 

13. The total number of digits used in numbering the pages of a book having 460 pages is ?
a)850
b)1860
c)2050
d)1272
e)2570

Ans. Total number of digits = (No. of digits in 1-digit page nos. + No. of digits in 2-digit page nos. + No. of digits in 3-digit page nos.)
= (1 x 9 + 2 x 90 + 3 x 361}= (9 + 180 + 1083) = 1272.

 

14. A builder built a fence around his square plot. He used 54 fence poles on each side of the square. How many poles did he need altogether?
a)216
b)230
c)212
d)210
e)222

Ans.

Since each pole at the corner of the plot is common to its two sides, so we have:

Total number of poles needed = 54 x 4 - 4 = 216 - 4 = 212.

 

15. Five years ago, the average age of a family of 3 members was 35 years. A child has been born, due to which the average age of the family is 31 years today. What is the Present age of the child ?
a)4
b)6
c)3
d)7
e)5

Ans.

Average age of the family of 3 members

4 years ago = 30 years

Sum of the ages of the 3 members now = (35 + 5) * 3 = 120 years

Average age of the family of 4 members now = 31 years

Sum of the ages of the 4 numbers now = 31 * 4 = 124 years

Age of child = 124 - 120 = 4 years.

16. The sum of two numbers is 312 and their H.C.F is 26 . The numbers are ?

a)24,242

b)26,296

c)52,562

d)26,286

e)28,274

Ans.

Let the numbers be 26a and 26b
Then 26a+ 26b =312
so, a + b = 312/26 = 12
Value of co-primes a and b are (1, 11)  (5, 7)
Numbers are (26*1, 26*11) = (26,286)

17. A boy was asked to find the value of 7/12 of a sum of money. Instead of multiplying the sum by 7/12 he divided it by 7/12 and thus his answer exceeded the correct answer by 95. Find the correct answer ?
a)34
b)65
c)52
d)49
e)42

Ans. 
Let sum = A
12/7 A – 7A/12 = 95
(144A – 49A)/84   = 95
 A = 84
 Therefore correct answer is 7/12 A = 7/12 * 84 = 49

18. A number consists of two digits whose sum is 7. If 27 is added to the number, then the digits change their places. What is the number?
a)32
b)53
c)35
d)25
e)46

Ans.  
Let the two digits be 'a' and 'b'.
so a + b = 7 -----------(1)
(a*10 + b) + 27 = (10*b + a) 
=> a - b = -3 --------(2)
adding (1) + (2)
2a = 4 => a=2 , b=5
so number 25

19.Six poles A, B, C, D, E and F are put in such a way that the distance between the next two decreases by 3 meter. The distance between the first two poles, A and B, is 30 meteres. If a monkey hops from pole F to pole C, then how much distance did it cover?
a)58m
b)68m
c)56m
d)72m
e)63m

Ans. 
Required distance = Distance between F and C = ( 18+ 21+ 24+ 27) m= 63m

20. Three train tickets from city X to Y and Four tickets from city X to Z cost 98 but Four tickets from city X to Y and Two tickets from city X to Z cost 119. What are the cost for cities Y and Z from X?
a)Rs 10, Rs 12
b)Rs 26, Rs 5
c)Rs 20, Rs 7
d)Rs 28, Rs 9
e)Rs 18, Rs 5

Ans. 

Let A be the fare of city X to city Y and 

B be the fare of city X to city Z.

Then, 3A + 4B = 98 ... (i)      and        4A + 3B = 119 ... (ii)

Multiplying (i) by 4 and (ii) by 3 and subtracting,we get: 7B = 35 or B = 5.

Putting B = 5 in (i), we get : A = 26.

ie, A = Rs.26  &  B = Rs.5