Quantitative Aptitude - Arithmetic Ability Questions

Q:

In a Plane there are 37 straight lines, of which 13 pass through the point A and 11 pass through the point B. Besides, no three lines pass through one point, no lines passes through both points A and B , and no two are parallel. Find the number of points of intersection of the straight lines.

A) 525 B) 535
C) 545 D) 555
 
Answer & Explanation Answer: B) 535

Explanation:

The number of points of intersection of 37 lines is C237. But 13 straight lines out of the given 37 straight lines pass through the same point A.

 

Therefore instead of getting C213 points, we get only one point A. Similarly 11 straight lines out of the given 37 straight lines intersect at point B. Therefore instead of getting C211 points, we get only one point B.

 

 Hence the number of intersection points of the lines is C237-C213-C211 +2 = 535

 

 

 

 

 

 

 

  

Report Error

View Answer Report Error Discuss

Filed Under: Permutations and Combinations
Exam Prep: CAT , Bank Exams , AIEEE
Job Role: Bank PO , Bank Clerk

43 24159
Q:

If the standard deviation of a population is 3, what would be the population variance?

 

A) 9 B) 6
C) 8 D) 15
 
Answer & Explanation Answer: A) 9

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Probability
Exam Prep: Bank Exams

10 24141
Q:

What value should come in place of the question mark (?) in the following question?

?2% of 650 = 202 + 42

A) 8 B) 64
C) 8 D) 642
 
Answer & Explanation Answer: A) 8

Explanation:

?2=400+16650x100?= 8

Report Error

View Answer Report Error Discuss

0 24091
Q:

The ratio of investments of two partners is 11:12 and the ratio of their profits is 2 : 3. If A invested the money for 8 months , find for how much time B invested his money.

Answer

Suppose A invested Rs.11 for 8 months and B invested Rs. 12 for x months.


\inline \therefore Ratio of investments of A and B


                  = (11 x 8) : (12 x x)


                  = 88 : 12x 


\inline \therefore \inline \frac{88}{12x}=\frac{2}{3}\Rightarrow x=11

Report Error

View answer Workspace Report Error Discuss

Subject: Partnership

26 24084
Q:

In what ratio should water and wine be mixed so that after selling the mixture at the cost price a profit of 33.33% is made?

A) 1:4 B) 1:3
C) 2:3 D) 3:4
 
Answer & Explanation Answer: B) 1:3

Explanation:

33.33% profit means there is one part water and 3 part is pure wine. so the required ratio of water and wine in the mixture is 1:3

Report Error

View Answer Report Error Discuss

Filed Under: Profit and Loss

64 24076
Q:

Four ladies A, B, C and D and four gentlemen E, F, G and H are sitting in a circle round a table facing each other.

Directions:

(1) No two ladies or two gentlemen are sitting side by side.

(2) C, who is sitting between G and E is facing D.

(3) F is between D and A and is facing G.

(4) H is to the right of B.

Question:

1. Who are immediate neighbours of B?

2. E is facing whom?

A) G & H , H B) F & H , B
C) E & F , F D) E & H , G
 
Answer & Explanation Answer: A) G & H , H

Explanation:

From the directions given : 

f11482726547.png image

From the fig. it is clear that 

1) neighbours of B are G , H.

2) E is facing H.

Report Error

View Answer Report Error Discuss

Filed Under: Permutations and Combinations
Exam Prep: CAT
Job Role: Bank PO

22 24056
Q:

The difference between the simple interest received from two different sources on Rs.1500 for 3 years is Rs.13.50. The difference between their rates of interest is

A) 0.1% B) 0.2%
C) 0.3% D) 0.4%
 
Answer & Explanation Answer: C) 0.3%

Explanation:

(1500 x R1 x 3)/100 

=> 4500 (R1-R2) = 1350 

=> (R1-R2)= 1350/4500 = 0.3 %

Report Error

View Answer Report Error Discuss

Filed Under: Simple Interest
Exam Prep: GRE

48 24045
Q:

Find the appropriate relation for quantity 1 and quantity 2 in the following question:

 

An artificial kund is filled by three pipes with uniform flow. The first two pipes operating simultaneously fill the kund at the same time during which the kund is filled by the third pipe alone. The second pipe fills the kund 5 hours faster than the first pipe and 4 hours slower than the third pipe.

Quantity 1: The time required by the first pipe?

Quantity 2: Time taken by all three pipes to fill the Kund simultaneously

A) Quantity 1 > Quantity 2 B) Quantity 1 ≥ Quantity 2
C) Quantity 1 < Quantity 2 D) Quantity 1 ≤ Quantity 2
 
Answer & Explanation Answer: A) Quantity 1 > Quantity 2

Explanation:

Quantity 1:
Let the first pipe alone takes x hours to fill the
tank.
⇒The second and third pipes will take (x-5) and
(x-9) hours respectively.
According to the given information:
∴ 1x-9

⇒ (x-9)(2x-5) = x2 – 5x
⇒ 2x2 – 5x – 18x + 45 = x2 – 5x
⇒ x
2 -18x + 45 = 0
⇒ (x-15) (x-3) = 0
⇒ x = 15, 3

The first pipe can take 15 hours to fill the kund.
∵ 3 hours doesn’t satisfy the statement.
Quantity 2:
∴ Time taken by second pipe = x-5
⇒ Time taken by second pipe = 15-5 = 10hours
∴ Time taken by third pipe = x -9
⇒ Time taken by third pipe = 15- 9 = 6 hours
Now,

Net part filled in 1 hour = 115+110+16
⇒ Net part filled in 1 hour = 4+6+1060
⇒Net part filled in 1 hour = 2060=13
∴The Kund will be full in 3/1 hours if all the pipes are opened simultaneously
Now, comparing
15 > 3
Thus, Quantity 1 > quantity 2

Report Error

View Answer Report Error Discuss

2 24011