Quantitative Aptitude - Arithmetic Ability Questions

Q:

Two numbers are respectively 20% and 50% more than a third number. The ratio of the two numbers is:

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

Explanation:

Let the third number be x.

Then, first number = 120% of x =120x/100 = 6x/5  


Second number =150% of x = 150x/100 = 3x/2

Ratio of first two numbers = 6x/5 : 3x/2 = 12x : 15x = 4 : 5

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions

622 184098
Q:

Insert the missing number.

16, 33, 65, 131, 261, (....)

A) 523 B) 521
C) 613 D) 721
 
Answer & Explanation Answer: A) 523

Explanation:

Each number is twice the preceding one with 1 added or subtracted alternatively.

So, the next number is (2 x 261 + 1) = 523.

Report Error

View Answer Report Error Discuss

Filed Under: Odd Man Out

45 170276
Q:

Simplify the following :

373+353+283-3x37x35x28372+352+282-37x35-35x28-37x28 ?

A) 100 B) 1
C) 4 D) 0
 
Answer & Explanation Answer: A) 100

Explanation:

Given 373+353+283-3x37x35x28372+352+282-37x35-35x28-37x28

 

It is in the form of

 a3+b3+c3-3abca2+b2+c2-ab-bc-ca= a + b + c

 

Here a = 37, b = 35 & c = 28 

 

=> a + b + c = 37 + 35 + 28 = 100

 

 

 

Therefore,   = 100

Report Error

View Answer Report Error Discuss

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

20 158383
Q:

If 20% of a = b, then b% of 20 is the same as :

A) 4% of a B) 6% of a
C) 8% of a D) 10% of a
 
Answer & Explanation Answer: A) 4% of a

Explanation:

20% of a = b 

=> (20/100) * a = b 

 b% of 20 =(b/100) x 20 = [(20a/100)  / 100] x 20= 4a/100 = 4% of a.

Report Error

View Answer Report Error Discuss

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

1378 155779
Q:

92613 x 62742241 = ? + 89

Find the value of '?'

A) 166251 B) 166259
C) 166252 D) 166253
 
Answer & Explanation Answer: C) 166252

Explanation:

Given 92613 x 62742241 = ? + 89

 

Using unit digit method,

 

On LHS,

 

1 x 1 x 1 = 1

 

sqrt of last digit 1 => it must end with either 9 or 1

 

so now

 

1 x 1 = 1

 

1 x 9 = 9

 

On RHS,

 

? + 89

 

=> ? = ...1 - 89 = last digit is 11- 9 = 2

 

or

 

=> ? = ...9 - 89 = last digit is 9 - 9 = 0

 

Here in the options last digit 2 is option C.

Report Error

View Answer Report Error Discuss

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

22 155416
Q:

A student multiplied a number by 3/5 instead of 5/3, What is the percentage error in the calculation ?

A) 54 % B) 64 %
C) 74 % D) 84 %
 
Answer & Explanation Answer: B) 64 %

Explanation:

Let the number be x.

Then, ideally he should have multiplied by  x by 5/3. Hence Correct result was x * (5/3)= 5x/3. 

 

By mistake he multiplied x by 3/5 . Hence the result with error  = 3x/5 

Then, error = (5x/3 - 3x/5) = 16x/15 

Error %  = (error/True vaue) * 100 = [(16/15) * x/(5/3) * x] * 100 = 64 %

Report Error

View Answer Report Error Discuss

Filed Under: Percentage

814 154838
Q:

Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?

A) 1/2 B) 3/5
C) 9/20 D) 8/15
 
Answer & Explanation Answer: C) 9/20

Explanation:

Here, S = {1, 2, 3, 4, ...., 19, 20}.

Let E = event of getting a multiple of 3 or 5 = {3, 6 , 9, 12, 15, 18, 5, 10, 20}.

P(E) = n(E)/n(S) = 9/20.

Report Error

View Answer Report Error Discuss

Filed Under: Probability

321 154430
Q:

A grocer has a sale of Rs 6435, Rs. 6927, Rs. 6855, Rs. 7230 and Rs. 6562 for 5 consecutive months. How much sale must he have in the sixth month so that he gets an average sale of Rs, 6500 ?

A) 4991 B) 5467
C) 5987 D) 6453
 
Answer & Explanation Answer: A) 4991

Explanation:

 Total sale for 5 months = Rs. (6435 + 6927 + 6855 + 7230 + 6562) = Rs. 34009.

 Required sale = Rs.[(6500 x 6) - 34009]

= Rs. (39000 - 34009) 

= Rs.  4991.

Report Error

View Answer Report Error Discuss

Filed Under: Average

401 152433