Problems on Numbers - General Questions

The sum of two numbers is 64 and their difference is 12. What is the larger number?

The sum of three consecutive integers is 24. What is the largest of them?

The sum of two numbers is 35 and their product is 250. What is the sum of their squares?

The difference between a two-digit number and the number obtained by interchanging its digits is 18. What is the difference between the two digits?

When 3 times a number is increased by 4, the result is 19. What is the number?