Night Class: 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 

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?
(e)None of these 
3.If the marked price of 30 articles is equal to selling price of 40 articles, then find the % discount?
(d) 20%
(e)None of these 
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 
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 
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 
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 
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:
(e)None of these 
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 
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