Learn and practice Problems on number with easy explaination and shortcut tricks. All questions and answers on number covered for various Competitive Exams.

Solve Problems:

1) If 30% of a certain number is 12.6, what is the number?

8) The sum of two consecutive odd numbers in a set of three consecutive odd numbers is 5 more than the third number. What is the second of these numbers?

Let the numbers be x, x+2, x+4, ∴ (x + x+2) – (x+4) = 5 2x + 2 – x – 4 = 5 X – 2 = 5 X = 5+2 = 7 ∴ Second number: 7+2= 9

9) The ratio between a two-digit number and the sum of the digits of that number is 4:1. If the digit in the unit place is 3 more than the digit in the ten’s place, what is that number?

10) The difference between a two-digit number and the number obtained by interchanging the digits is 27. What is the difference between the digits of the number?

Let the ten’s digit be = x Unit’s digit = y So, the number is = 10x +y The number obtained by interchanging the digits = 10y + x According to the question: (10x + y) – (10y + x) = 27 10x + y – 10y – x = 27 9x – 9y = 27 (x – y) = 3 ∴The difference between the digits of the numbers, i.e., (x – y) = 3.