When the length of each side of a square was reduced by 20%, its area became 16 square centimeters. What was the area of the original square?

Of three consecutive natural numbers, the square of the smallest is 308025 and the square of the next is 309136. What is the square of the largest?

The product of two consecutive odd numbers is 89999. What is their sum?

Ramu says to Raju, 'Your salary is 25% more than mine'. Raju replies, 'Your salary is ...... less than mine'. What percent did Raju say?

When the first digit and the last digit of a five-digit number, which is a multiple of 72, are erased, we get 679. What is the number?