The ratio of coins of 50 paisa, 25 paisa, and 10 paisa is 4:3:2. Find the total amount if the number of coins is 90.

A number is divided into 3 parts A, B and C in the ratio of 3:2:1. If half of the number is 54, then find the square of the smallest number?

Average of 21 number is 36. If the average of first 12 numbers is 15, then find the average of remaining 9 number?

In a circle, difference between the circumference and radius is 37 cm. Find the area (in cm²) of the circle?

0.8% of a number is 31, then find the number.

Ratio of CP and SP is 12:13, then the profit percent is?

Bananas are bought at 3 for Rs. 2 and sold at 5 for Rs. 4. Find the gain or loss percent.

Find the sum of 2x terms of the series ( 1² - 2² + 3² - 4² + ___ )