Quantitative Aptitude - Arithmetic Ability Questions

Q:

If a card is drawn at random from a pack of 52 cards,what is the chance of getting a spade or ace?

A) 0.25 B) 5/13
C) 0.20 D) 4/13
 
Answer & Explanation Answer: D) 4/13

Explanation:

Number of spades in a standard deck of cards=13
Number of aces in a standard deck of cards=4
And,one of the aces is a spade.
So, 13 + 4 - 1 = 16 spades or aces to choose from.
Therfore,probabiltiy of getting a spade or an ace=16/52=4/13

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Filed Under: Probability

18 17980
Q:

4 kg of a metal contains 1/5 copper and rest in Zinc. Another 5 kg of metal contains 1/6 copper and rest in Zinc.The ratio of Copper and Zinc  into the mixture of these two metals:

A) 49 : 221 B) 39:231
C) 94:181 D) None of these
 
Answer & Explanation Answer: A) 49 : 221

Explanation:

Copper in 4 kg = 4/5 kg          and      Zinc in 4 kg = 4 x (4/5) kg

 

Copper in 5 kg = 5/6 kg          and      Zinc in 5 kg = 5 x (5/6) kg

 

Therefore, Copper in mixture = 45+56=4930 kg

 

and  Zinc in the mixture = 165+256=22130kg

 

Therefore the required ratio = 49 : 221

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Filed Under: Alligation or Mixture

30 17979
Q:

An equilateral triangle is described on the diagonal of a square. What is the ratio of the area of the triangle to that of the square?

A) 1:2 B) 1:3
C) 2:3 D) 3^(1/2) :2
 
Answer & Explanation Answer: D) 3^(1/2) :2

Explanation:

area of a square = a² sq cm

 

length of the diagonal = 2a cm

 

area of equilateral triangle with side  2a= 34*2a2
required ratio = 34*2a2:a2=3:2

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

14 17974
Q:

The true discount on Rs. 2562 due 4 months hence is Rs. 122. The rate percent is?

A) 12% B) 13%
C) 15% D) 14%
 
Answer & Explanation Answer: C) 15%

Explanation:

P.W = 2562-122 =Rs.2440   

Rate = [100 x 122] / [2440 x (1/3)] =15%

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Filed Under: True Discount

16 17966
Q:

A hollow iron pipe is 21 cm long and its external diameter is 8 cm. If the thickness of the pipe is 1 cm and iron weighs 8g/cu.cm, then the weight of the pipe is

A) 3.6 kg B) 3.696 kg
C) 36 kg D) 36.9 kg
 
Answer & Explanation Answer: B) 3.696 kg

Explanation:

External radius = 4 cm 

Internal radius = 3 cm 

Volume of iron = 227×42-32×21cm3462cm3   

Weight of iron = (462 x 8)gm = 3696 gm = 3.696 kg

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28 17940
Q:

A sum of money invested at compound interest amounts to Rs. 800 in 3 years and to Rs. 840 in 4 years. The rate of interest per annum is

A) 6% B) 4%
C) 5% D) 7%
 
Answer & Explanation Answer: C) 5%

Explanation:

S.I. on Rs.800 for 1 year

=Rs[840 - 800]

= Rs.40

 

Rate

=(100x40/800x1)%

= 5%

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Filed Under: Compound Interest
Exam Prep: Bank Exams
Job Role: Bank PO

15 17920
Q:

If (89)2 is added to the square of a number, the answer so obtained is 16202. What is the (1/26) of that number?

A) 5.65 B) 2.7
C) 3.5 D) 6.66
 
Answer & Explanation Answer: C) 3.5

Explanation:

Let the number is = x

(89)2 + x2 = 16202

x2 = 8281

x = 91

=> (1/26) of 91 = 3.5

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Filed Under: Square Roots and Cube Roots
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Analyst , Bank Clerk , Bank PO

18 17918
Q:

Two pipes A and B can fill a tank in 24 hours and 1717 hours respectively. Harihar opened the pipes A and B to fill an empty tank and some times later he closed the taps A and B , when the tank was supposed to be full. After that it was found that the tank was emptied in 2.5 hours because an outlet pipe "C" connected to the tank was open from the beginning. If Harihar closed the pipe C instead of closing pipes A and B the remaining tank would have been filled in :

A) 2 hours B) 8 hours
C) 6 hours D) 4 hours
 
Answer & Explanation Answer: B) 8 hours

Explanation:

Efficiency of Inlet pipe A = 4.16%       10024 

 

Efficiency of Inlet pipe B = 5.83%      1001717  

 

Therefore, Efficiency of A and B together = 100 %   

 

Now, if the efficiency of outlet pipe be x% then in 10 hours the capacity of tank which will be filled = 10 *  (10 - x)

 

Now, since this amount of water is being emptied by 'C' at x% per hour, then

 

 10x10-xx=2.5 hrs 

 => x = 8 

 

Therefore, in 10 hours 20% tank is filled only. Hence, the remaining 80% of the  capacity will be filled by pipes A and B  in 80/10 = 8 hours 

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Filed Under: Time and Work
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Bank Clerk , Bank PO

38 17890