Quantitative Aptitude - Arithmetic Ability Questions

Q:

The ratio of the ages of Maala and Kala is 4 : 3. The total of their ages is 2.8 decades. The proportion of their ages after 0.8 decades will be [1 Decade = 10 years]

A) 4:3 B) 12:11
C) 7:4 D) 6:5
 
Answer & Explanation Answer: D) 6:5

Explanation:

Let, Maala’s age = 4A and Kala’s age = 3A
Then 4A + 3A = 28
A = 4
Maala’s age = 16 years
and Kala’s age = 12 years
Proportion of their ages after 8 is = (16 + 8) : (12 + 8)
= 24 : 20
= 6 : 5

Report Error

View Answer Report Error Discuss

Filed Under: Problems on Ages

41 18336
Q:

Two numbers are 35% and 42% are less than a third number .How much percent is the second number less than the first ?

A) 10.769 % B) 11.23 %
C) 10.4 % D) 9.87 %
 
Answer & Explanation Answer: A) 10.769 %

Explanation:

I      II     III

65   58   100

65 -------- 7
100 ------ ?  => 10.769%

Report Error

View Answer Report Error Discuss

Filed Under: Percentage
Exam Prep: AIEEE , Bank Exams , CAT , GATE
Job Role: Bank Clerk , Bank PO

12 18326
Q:

A circular swimming pool is surrounded by a concrete wall 4ft wide. If the area of the concrete wall surrounding the pool is 11/25 that of the pool, then the radius of the pool is?

A) 10ft B) 20ft
C) 30ft D) 40ft
 
Answer & Explanation Answer: B) 20ft

Explanation:

let the radius of the pool be Rft

 

Radius of the pool including the wall = (R+4)ft

 

Area of the concrete wall = πR+42-R2=πR+4+RR+4-R = 8πR+2 sq feet

 

=> 8πR+2 = 1125πR2 =>11R2 =200R+2

 

Radius of the pool R = 20ft

Report Error

View Answer Report Error Discuss

Filed Under: Area
Exam Prep: Bank Exams
Job Role: Bank PO

19 18322
Q:

From a group of 7 men and 6 women, five persons are to be selected to form a committee so that at least 3 men are there on the committee. In how many ways can it be done?

A) 564 B) 735
C) 756 D) 657
 
Answer & Explanation Answer: C) 756

Explanation:

We may have (3 men and 2 women) or (4 men and 1 woman) or (5 men only). 

 

Required number of ways= 7C3*6C2+7C4*6C1+7C5 = 756.

Report Error

View Answer Report Error Discuss

11 18310
Q:

What is the smallest number by which 2880 must be divided in order to make it into a perfect square ?

A) 2 B) 3
C) 4 D) 5
 
Answer & Explanation Answer: D) 5

Explanation:

By trial and error method, we get
2880/3 = 960 is not a perfect square
2880/4 = 720 is not a perfect square
2880/5 = 576 which is perfect square of 24
Hence, 5 is the least number by which 2880 must be divided in order to make it into a perfect square.

Report Error

View Answer Report Error Discuss

Filed Under: Numbers
Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Analyst , Bank Clerk , Bank PO

14 18291
Q:

The banker's discount on a certain sum due 2 years hence is11/10of the true discount.

The rate percent is:

A) 10% B) 7%
C) 8% D) 5%
 
Answer & Explanation Answer: D) 5%

Explanation:

Let T.D. be Re. 1.

Then, B.D. = Rs.11/10= Rs. 1.10.

Sum = Rs. (1.10*1)/(1.10-1) = Rs. (110/10)= Rs. 11.

S.I. on Rs. 11 for 2 years is Rs. 1.10

Rate = [(100 x 1.10)/(11 x 2 )]% = 5%.

Report Error

View Answer Report Error Discuss

Filed Under: Banker's Discount

7 18265
Q:

One type of liquid contains 25 % of benzene, the other contains 30% of benzene. A can is filled with 6 parts of the first liquid and 4 parts of the second liquid. Find the percentage of benzene in the new mixture.

A) 27 % B) 26 %
C) 29 % D) 21 %
 
Answer & Explanation Answer: A) 27 %

Explanation:

Let the percentage of benzene = X
(30 - X)/(X- 25) = 6/4 = 3/2
=> 5X = 135  
X = 27

So, required percentage of benzene = 27 %

Report Error

View Answer Report Error Discuss

30 18251
Q:

A man covers half of his journey by train at 60 km/hr, half of the remaining by bus at 30 km/hr and the rest by cycle at 10 km/hr. Find his average speed during the entire journey?

A) 32 kmph B) 20 kmph
C) 18 kmph D) 24 kmph
 
Answer & Explanation Answer: D) 24 kmph

Explanation:

Let the total distance of the journey of a man = d kms

Now, the average speed of the entire journey = dd120 + d120 + d40  = 24 kmph.

Report Error

View Answer Report Error Discuss

30 18250