Quant Quiz

1. A pipe can empty a tank in 40 minutes. A second pipe with diameter twice much as that of the first is also attached with the tank to empty it. The two together can empty the tank in:

(a)8.5 minutes   

(b)13.33 minutes

(c)30 minutes   

(d)8 minutes

(e)None of these 

1. (d) 

Here volume of water emptied by the second pipe will be 4 times to that of first 

Hence, Time take will be 1/4 of the first pipe. 

When both the pipes are open the part of the tank emptied in 1 minute

= 1/40 + 1/10 = 1/8 

Hence the tank will be emptied in 8 minutes.

2. A can do 1/2 of a piece of work in 5 days. B can do 3/5 of the same work in 9 days and C can do 2/3 of that work in 8 days. In how many days can three of them together do the work?

(a)3    

(b)5

(c)4.5  

(d)4

(e)None of these 

2. (d) 

(A+B+C) one day’s work =1/10+ 1/15+1/12= 1/4

Hence together they complete the work in 4 days

3. If the marked price of 30 articles is equal to selling price of 40 articles, then find the % discount?

(a)25%   

(b)33.33%

(c)75%   

(d) 20%

(e)None of these 

3. (a) 

MP of 30 = SP 40

MP/SP = 40/30

Discount = (10/40) * 100= 25%

4. The length of one side of a rhombus is 6.5 cm and its altitude is 10 cm. If the length of its one diagonal is 26 cm, the length of the other diagonal will be:

(a)5 cm   

(b)6.5 cm

(c)10 cm    

(d)26 cm

(e)None of these 

4. (a)  

Area =base * height =6.5*10 = 65cm2

Let the diagonal of rhombus be d1 and d2.

Area = 1/2 d1d2 = 65

= ½* 26* d2 = 65

d2 = 5

5. The average age of 30 boys in a class is 15 Years. One boy, aged 20 years, left the class, but two new boys come in his place whose ages differ by 5 years. If the average age of all the boys now in the class becomes 15 years, the age of the younger new comer is:

(a)20 year    

(b)15 year

(c)40 year    

(d)8 year

(e)None of these 

5. (b) 

Let the age of younger one be x and other is x+5

 so, x+(x+5) = (31*15)-(30*15-20)=35 

x= 15

6. The areas of two similar triangles are 81 cm2 and 49 cm2 respectively. The ratio of their corresponding heights is:

(a)9 : 7    

(b)7 : 3

(c)3 : 7    

(d)81 :49

(e)None of these 

6. (a)

h1/h2=b1/b2

1/2*b1*h1∶1/2*b2*h2 = 81 : 49

h1^2 ∶h2^2=81∶49

h1 : h2 = 9 : 7

7. If a : b = 2 : 3 and b : c = 4 : 5, find a^2 : b^2 : c^2 ?

(a)4 : 9 : 45   

(b)16 : 36 : 45

(c)16 : 36 : 20  

(d)4 : 36 : 40

(e)None of these 

7. (e) 

a:b:c = 8:12:15

a^2: b^2 :c^2: =64:144:225

8. A dealer offer a discount of 10% on the marked price of an article and still makes a profit of 20%. If its marked price is Rs. 800, then the cost price of the article is:

(a)Rs.900    

(b)Rs.800

(c)Rs.700    

(d)Rs.600

(e)None of these 

8. (d)

SP = 800 * 90/100 = 720

CP = 720 * 100/120 = 600

9. The capacities of two hemispherical vessels are 6.4 litres and 21.6 litres. The ratio of their inner radii is

(a) 4 : 9  

(b) 16 : 81

(c) √2:√3  

(d) 2 : 3

(e) None of these 

9. (d)

r13 : r23 = 6.4 : 21.6

r1 : r2 = 4 : 6 = 2 : 3

10. Pipe A alone can fill a tank in 8 hours. Pipe B alone can fill it in 6 hours. If both the pipes are opened and after 2 hours, pipe A is closed, then the other pipe will fill the tank in

(a) 6 hours  

(b) 3.5 hours

(c) 4 hours  

(d) 2.5 hours

(e) None of these 

10. (d)

If both pipes are open,

1/8+1/6=7/24

For 2 hours = 2 * 7/24 = 7/12 tank is filled

Remaining empty tank = 1- 7/12 = 5/12

Therefore, B can fill the remaining tank in 5/12 * 6 = 2.5 hours