Quantitative Aptitude Set-3

                              Quantitative Aptitude Quiz

Hello Everyone,
                     This Post contains few questions on Mixture and allegation which can be asked in various competitive exams. Practice makes a man perfect. Keep Practicing, Keep raising.

Q1- If the average weight of a class of students is 15 and the average weight of another class of students is 30, then find the ratio of the students of the fist class to the another class of 30 students when the average wt of both the class is 25:

A- 1:2  B- 2:1 C- 1:3 D- 3:4

Soln:

15_______________________30

_________25______________

X_______________________y

== > (30-25)/(25-15)=x/y ==> x:y =1:2 ans

Q2- Two varieties of soda water with different prices is mixed in the ratio of 2:3 . The price of first soda water is rs 50 for 5 liter while the price of second soda water is rs 15 per liter, respectively. The price of 5 liter mixture is :

A- 60 B- 65 C- 50 D- 70

Soln: We use allegation method when the prices are per unit.

So price of first soda water / liter= 10

10__________15

____x________
2__________3

== >(15-x)/(x-10)= 2/3  ===> x=13 /liter , for 5 liter= 65

Q3- Amit travels 30 minutes at the speed of 25 km/hr . Further he travels 20 minutes at the speed of 40 km/hr . Find his average speed

A- 25kmph B- 30 kmph C- 31 kmph D- NOTA

25_________40

____x______
30______20

== >(40-x)/(x-25)= 3/2 == >x= 31

Q4- Modern electronic shop sold the 30% hardware at 50% profit and 90% software at the profit of 10%. The avg  profit % of the modern electronic shop, if its sells only these two kind of things

A- 15 B- 20 C- 25 D- 45

10_________50

____X_______

90_______30

50-x/ (x-10)= 90/30=3/1

== > 50-x = 3x- 30 == > 4x= 80== >x=20

Q5- A man bought a mobile and a laptop for Rs. 78000. He sold the mobile at a gain of 25% and the laptop at a loss of 15%, thereby gaining 5% on the whole. Find the cost price of mobile...

1) Rs. 39000 2) Rs. 34000 3) Rs. 30000 4) Rs. 38000 5) Rs. 32000

Soln: Mobile =X , Laptop= Y

-15___________25

_______5______
y___________x

== > (25-5)/ {5 –(-15)} = y/x

== >20/20= y/x == >x=y  also x+y= 78000 ==> CP of mobile= 39000

Q6- The milk and water in two vessels A and B are in the ratio 4:3 and 2:3 respectively. In what ratio the liquids in both the vessels be mixed to obtain a new mixture in vessel c consisting half milk and half water?

A- 8:3 B-7:5 C- 7:3 D- 2:3

Soln: Milk in A = 4/7 , Milk in B= 2/ 5 , Milk in mix= 1/2  {since in mix. Milk=water}

4/7 _____________2/5

______1/2________

X___________y

{2/5-1/2}/{1/2- 4/7} =x/y = 7:5 ans

Q7- How many kilograms of sugar costing Rs. 9 per kg must be mixed with 27kg of sugar costing Rs.7 per kg so that there may be gain of 10% by selling the mixture at Rs.9.24 per kg?

A- 60 B- 63 C- 50 D- 77

Soln: SP= 9.24 , and profit =10%== > CP= 9.24/1.1= 8.4

7_____________9

_____8.4______

Y_________x  

=== > y/x = (9-8.4)/(8.4-7)= 0.6/1.4= 3:7

Given first  type of sugar is 27 kg. so 3--------27== >7== 27/3 *  7= 63.

Q8- A man travelled a distance of 90Km in 9 hours partly on foot at 8 kmph and partly on bicycle at 17 kmph. Find the distance travelled on foot.

A- 46 , B- 56 , C- 62 D- 52

Soln: Avg speed = 90/9= 10

8____________________17

_________10__________

X__________________y

x/y= (17-10)/(10-8)= 7/2 == > of 9 hours he travelled 7 hour on foot== > Distance covered= 7*8=56

Q9- Some amount out of 6000/- was lent out at 10% pa and the rest amount at 20% pa. thus total interest in 4 years was rs 3400. What was the amount lent @ 10%?

A- 2500, B- 3000, C- 3500, D- 4000

Soln: 4 yr interest= 3400== >one yr rate= 3400/4=850

850 is what % of 6000== >850/6000 * 100= 85/6%

Let amount lent at 10%=x and at 20%=y

10_____________20

______85/6_____
x____________y

{20-85/6}/ {85/6-10} = x/y==> 7:5

There fore amount lent at 10%= 7/12* 6000= 3500

Q10- A dishonest milkman professes to sell his milk at cost price but he mixes it with water and thereby gains 25%. The percentage of water in the mixture is:

A- 4% , B- 25/4% , C- 20% D- 15%
Soln: CP of 1 liter milk=1, SP of mix= 1 , given 25% profit==>CP= 1/1.25= 0.8, CP of water= 0

0____________1

_____0.8______

X___________y

x/y = 0.2/0.8= 1/4

% of water= x/(x+y)= 1/5 = 20%

Quiz Prepared By- Che Sir 

Regards,

Classroom Team