The sum of two numbers is 45 and their ratio is 7: 8. The two numbers are:

Simplify : $$ {(2x)^{2}-(2y)^{2}-(4x)^{2}}$$

The average of 8 readings is 24.3, out of which the average of the first two is 18.5 and that of next three is 21.2. If the sixth reading is 3 less than seventh and 8 less than eight, what is the sixth reading? 

Rahul plans to buy a scooter for his sister for which he saves Rs. 15625 at the start of every year for 3 year. If the rate of CI is 4% pa. then amount at which he plans to buy the scooter is (in Rs.)

Find the exact value of the following question:

$$ \sqrt {123×8+2389-1164}=? $$

A shopkeeper bought 240 ton rice. He sold 4/5th is at 37.5% profit, then find at what percentage profit or loss he should sell remaining rice, so as to gain 25% on the whole transaction? 

The compound interest on a certain sum of money invested for 2 years at 5 % per annum is Rs. 328. The simple interest on the sum, at the same rate and for the same period will be 

If $$ P={{x^2-36}\over{x^2-49}}$$ and $$ Q={{x+6}\over{x+7}}$$ then the value of $$ {P\over{Q}}$$ is.