If a = 7, b = 5 and c = 3, then the value of $$a^2+b^2+c^2-ab-bc-ca$$ is 

In an examination 60% of the students passed in English and 70% in Mathematics, if 20% of the students failed in both the subjects and 2500 students passed in both the subjects, then what is the total number of candidates?

Each side of a square is 6 cm. On which a pyramid has been built, its slant height is 4: 2 cm. Find the total surface of the pyramid?

If $$ {(x^{3})^{3} × x^{5}\over{x^{4}}}=x^{n}$$ then find the value of n.

The value of Let $$\left({\sqrt {1875}\over\sqrt { 3888}}÷{\sqrt {1200}\over\sqrt {768}} \right)\ × \left({\sqrt {175}\over\sqrt {1792}} \right)\ $$. Then $$ \sqrt { x}$$ is equal to:

The marked price of an article is Rs 200. A profit of 25% is also earned by giving a discount of $$60{1\over2}\%$$ on the marked price. What is the cost price of that article?

A dozen pair of socks quoted at ₹ 80 are available at a discount of 10%. How many pairs of socks can be bought for ₹24?

The average of 30 numbers is 40 and that of the other 40 numbers is 30. The average of all the numbers is-