Quantitative Aptitude - Arithmetic Ability Questions

Q:

(a - b)2 + 2ab = ?

 

A) a2 - b2 B) a2 + b2
C) a2 - 4ab + b2 D) a2 -  2ab + b2
 
Answer & Explanation Answer: B) a2 + b2

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Simplification
Exam Prep: Bank Exams

3 83369
Q:

At what time between 5 and 6 o' clock are the hands of a 3 minutes apart ?

A) 24min B) 12min
C) 13min D) 14min
 
Answer & Explanation Answer: A) 24min

Explanation:

In this type of problems the formuae is
(5*x+ or - t)*12/11
Here x is replaced by the first interval of given time. Here x is 5.
t is spaces apart

  Case 1 : (5*x + t) * 12/11

 (5*5 + 3) * 12/11

 28 * 12/11 = 336/11= 31511 min

therefore the hands will be 3 min apart at 31 5/11 min past 5.

Case 2 : (5*x - t) * 12/11

(5*5 -3 ) * 12/11

 22 *12/11 = 24 min 

 therefore the hands will be 3 min apart at 24 min past 5

Report Error

View Answer Report Error Discuss

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

200 83362
Q:

 A pupil's marks were wrongly entered as 83 instead of 63. Due to that the average marks for the class got increased by half. The number of pupils in the class is :

A) 45 B) 40
C) 39 D) 37
 
Answer & Explanation Answer: B) 40

Explanation:

Let there be x pupils in the class.

Total increase in marks = (x * 1/2) = x/2.

x/2 = (83 - 63) => x/2 = 20 => x = 40.

Report Error

View Answer Report Error Discuss

Filed Under: Average

198 83254
Q:

What will come in place of question mark (?) in the following number series?

4, 3, 4, 7, 15, ?

A) 42 B) 44
C) 53 D) 56
 
Answer & Explanation Answer: B) 44

Explanation:

  4             3             4             7               15        ?
×1-1      ×1+1       ×2-1       ×2+1           ×3-1

 

15x3 - 1 = 45 - 1 = 44

Report Error

View Answer Report Error Discuss

Filed Under: Odd Man Out
Exam Prep: GATE , CAT , Bank Exams , AIEEE
Job Role: Bank PO , Bank Clerk

8 83231
Q:

Find the Odd One Out?

4, 6, 12, 30, 81, 315.

A) 6 B) 12
C) 81 D) 315
 
Answer & Explanation Answer: C) 81

Explanation:

Given the number series is 4, 6, 12, 30, 81, 315.

Here it follows a pattern that

4

4 x 1.5 = 6

6 x 2 = 12

12 x 2.5 = 30

30 x 3 = 90 not equals to 81

90 x 3.5 = 315

 

Hence the odd one in the series is 81.

Report Error

View Answer Report Error Discuss

9 82878
Q:

What was the day of the week on, 16th July, 1776?

A) Tuesday B) Wednesday
C) Monday D) Saturday
 
Answer & Explanation Answer: A) Tuesday

Explanation:

16th July, 1776 = (1775 years + Period from 1st Jan, 1776 to 16th July, 1776)

Counting of odd days :

1600 years have 0 odd day.

100 years have 5 odd days.

75 years = (18 leap years + 57 ordinary years) =  [(18 x 2) + (57 x 1)] = 93 (13 weeks + 2 days) = 2 odd days


1775 years have (0 + 5 + 2) odd days = 7 odd days = 0 odd day. 

 

Jan   Feb   Mar   Apr   May   Jun   Jul  

31 + 29 + 31 + 30 + 31 + 30 + 16 = 198 days= (28 weeks + 2 days) 

 

Total number of odd days = (0 + 2) = 2.  

Required day was 'Tuesday'.

Report Error

View Answer Report Error Discuss

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

691 82867
Q:

A sum of Rs.312 was divided among 100 boys and girls in such a way that the boy gets Rs.3.60 and each girl Rs. 2.40 the number of girls is

A) 35 B) 40
C) 45 D) 50
 
Answer & Explanation Answer: B) 40

Explanation:

Step (i): Let x be the number of boys and y be the number of girls.
Given total number of boys and girls = 100
x+y=100 -------------- (i)

Step (ii): A boy gets Rs. 3.60 and a girl gets Rs. 2.40
The amount given to 100 boys and girls = Rs. 312
3.60x + 2.40y = 312 -------------- (ii)

Step (iii):
Solving (i) and (ii)
3.60x + 3.60y = 360 --------- Multiply (i) by 3.60
3.60x + 2.40y = 312 --------- (ii)
1.20y = 48
y = 48 / 1.20
= 40

 Number of girls = 40

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions

343 82645
Q:

A merchant has 1000 kg of sugar part of which he sells at 8% profit and the rest at 18% profit. He gains 14% on the whole. The Quantity sold at 18% profit is

A) 400 kg B) 560 kg
C) 600 kg D) 640 kg
 
Answer & Explanation Answer: C) 600 kg

Explanation:

By the rule of alligation:

 

Profit of first part                         Profit of second part

 

 

So, ratio of 1st and 2nd parts = 4 : 6 = 2 : 3. 

 

Therefore, Quantity of 2nd kind = (3/5 x 1000)kg = 600 kg.

Report Error

View Answer Report Error Discuss

Filed Under: Alligation or Mixture

333 82343