The marked price of an article is 40% above its cost price. If its selling price is $$73{1\over 2}\%$$ of the marked price, then the profit percentage is

A can do 2% of a work in 4 days, B can do $$33{1\over 3}\%$$ of the same work in 10 days. They worked together for 9 days. C completed the remaining work in 6 days. B and C together will complete 75% of the same work in :

A spherical metallic shell with 6 cm external radius weighs 6688 g. What is the thickness of the shell if the density of metal is 10.5 g per cm3? (Take л = 22/7)

The expression   $${15(\sqrt { 10}+\sqrt { 5})\over \sqrt { 10}+\sqrt { 20}+\sqrt { 40}-\sqrt { 5}-\sqrt { 80}     }$$ is equal to:

A, B and C started a business. Twice the investment of A is equal to thrice the investment of B and also five times the investment of C. If the total profit after a year is 15.5 lakhs, then the share of B in the profit is (in lakhs):

The graphs of the equations 3x-20y-2=0 and 11x-5y+61=0 intersect at P(a,b). What is the value of (a² + b² — ab)/(a² — b² + ab)?

 If 3x²-5x+1=0, then the value of ( $$x^2+{1\over 9x^2}$$) is 

In a school, $${3\over 8}$$ of the number of students are girls and the rest are boys. One-third of the number of boys are below 10 years and $${2\over 3}$$ of the number of girls are also below 10 years. If the number of students of age 10 or more years is 260, then the number of boys in the school is: