Quantitative Aptitude - Arithmetic Ability Questions

Q:

In a group of 6 boys and 4 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be there?

A) 209 B) 290
C) 200 D) 208
 
Answer & Explanation Answer: A) 209

Explanation:

We may have (1 boy and 3 girls) or (2 boys and 2 girls) or (3 boys and 1 girl) or (4 boys). 

 

Required number of ways = 6C1*4C3+6C2*4C2+6C3*4C1+6C4  

6C1*4C1+6C2*4C2+6C3*4C1+6C2 = 209.

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11 22662
Q:

In a race of 1000 meters, A can beat B by 100 meters, in a race of 800 meters, B can beat C by 100 meters. By how many meters will A beat C in a race of 600 meters?

A) 125.5 meters B) 126.5 meters
C) 127.5 meters D) 128.5 meters
 
Answer & Explanation Answer: C) 127.5 meters

Explanation:

When A runs 1000 meters, B runs 900 meters and when B runs 800 meters, C runs 700 meters.

Therefore, when B runs 900 meters, the distance that C runs = (900 x 700)/800 = 6300/8 = 787.5 meters.

So, in a race of 1000 meters, A beats C by (1000 - 787.5) = 212.5 meters to C.

So, in a race of 600 meters, the number of meters by Which A beats C = (600 x 212.5)/1000 = 127.5 meters.

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Filed Under: Races and Games

30 22648
Q:

In what time will Rs. 1000 become Rs. 1331 at 10% per annum compounded annually?

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

Explanation:

Principal = Rs. 1000; Amount = Rs. 1331; Rate = 10% p.a. Let the time be n years. Then,
[ 1000 (1+ (10/100))^n ] = 1331 or (11/10)^n = (1331/1000) = (11/10)^3
n = 3 years

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

39 22627
Q:

What decimal of an hour is a second

A) .0028 B) .0027
C) .0026 D) .0025
 
Answer & Explanation Answer: B) .0027

Explanation:

1 / (60 * 60) = 1 / 3600 = .0027

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Filed Under: Decimal Fractions

53 22621
Q:

By mixing two qualities of pulses in the ratio 2: 3 and selling the mixture at the rate of Rs 22 per kilogram, a shopkeeper makes a profit of 10 %. If the cost of the smaller quantity be Rs 14 per kg, the cost per kg of the larger quantity is:

A) Rs 23 B) Rs 25
C) Rs 24 D) Nonof these
 
Answer & Explanation Answer: C) Rs 24

Explanation:

Cost Price of 5 kg = Rs.(14*2 + x*3) = (28 + 3x).

Sell price of 5 kg = Rs. (22x5) = Rs. 110.

[{110 - (28 + 3x)}/(28 + 3x) ]* 100 =10

[82-3x/28 + 3x]= 1 / 10

820 - 30x = 28 +3x 

33x = 792 

x = 24

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Filed Under: Profit and Loss

59 22612
Q:

The average age of 15 students of a class is 15 years. Out of these, the average age of 5 students is 14 years and that of the other 9 students is 16 years, The age of the 15th student is :

A) 11 B) 12
C) 13 D) 14
 
Answer & Explanation Answer: A) 11

Explanation:

Age of the 15th student = [15 * 15 - (14 * 5 + 16 * 9)] = (225-214) = 11 years.

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Filed Under: Average

20 22593
Q:

If 4/7 of P is equal to 12/14 of Q, then what is P : Q?

 

A) 15 : 8   B) 14 : 9  
C) 7 : 8   D) 3 : 2
 
Answer & Explanation Answer: D) 3 : 2

Explanation:
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Filed Under: Ratios and Proportions
Exam Prep: Bank Exams

2 22576
Q:

The largest measuring cylinder that can accurately fill 3 tanks of capacity 98, 182 and 266 litres each, is of capacity ?

A) 7 lts B) 14 lts
C) 98 lts D) 42 lts
 
Answer & Explanation Answer: B) 14 lts

Explanation:

To know the the measuring cylinder that can fill all the given capacities , they must be divisible by the required number.

98,182,266 all are divisible by 14
So  14 litres  is the largest cylinder that can fill all the given cylinders.

                                       (or)

The other method is take HCF of all given capacities i.e 98, 182 and 266.

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Filed Under: HCF and LCM
Exam Prep: AIEEE , Bank Exams , CAT , GATE
Job Role: Bank Clerk , Bank PO

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