(3x-7)³+(3x-8)³+(3x+6)³=3(3x-7)(3x-8)(3x+6)
Find the value of x ?

$$ {({1\over25})^{-1\over2}}+{({8\over 27})^{-1\over3}}$$

A man sold 18 cots for Rs.16800, gaining there by the cost price of 3 cots. The cost price of a cot is 

Find the average of the following set of numbers.
132, 148, 164, 128, 120, 136

A bank pays half-yearly compound interest at the rate of 5% p.a. . A person deposited Rs 1600 on January 1 and a similar amount on July 1 . Explain how much interest will be paid by the bank at the end of the year.

Rajesh goes to his office at the speed of 25km/hr and return to his home at the speed of 20 km/hr. If he takes total 9 hours, then what is the distance between his office and home?

In the given figure, the ratio of the area of the largest square to that of the smallest square is:

The average of 19 numbers is 24. If each number is multiplied by 3, what is the new average?