Home
Class 9
MATHS
A two digit number is obtained by multip...

A two digit number is obtained by multiplying the sum of the digits by 8. Also, it is obtained by multiplying the difference of the digits by 14 and adding 2. Find the number.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find a two-digit number based on the conditions provided. Let's break down the steps systematically. ### Step 1: Define the Variables Let: - \( x \) = the tens digit of the two-digit number - \( y \) = the units digit of the two-digit number Thus, the two-digit number can be expressed as: \[ 10x + y \] ### Step 2: Set Up the First Equation According to the problem, the two-digit number is obtained by multiplying the sum of the digits by 8. Therefore, we can write: \[ 10x + y = 8(x + y) \] Expanding this gives: \[ 10x + y = 8x + 8y \] Rearranging the equation leads to: \[ 10x + y - 8x - 8y = 0 \implies 2x - 7y = 0 \] This is our **first equation**: \[ 2x - 7y = 0 \quad \text{(Equation 1)} \] ### Step 3: Set Up the Second Equation The problem also states that the two-digit number is obtained by multiplying the difference of the digits by 14 and adding 2. Thus, we can write: \[ 10x + y = 14(x - y) + 2 \] Expanding this gives: \[ 10x + y = 14x - 14y + 2 \] Rearranging the equation leads to: \[ 10x + y - 14x + 14y - 2 = 0 \implies -4x + 15y - 2 = 0 \] This is our **second equation**: \[ 4x - 15y = -2 \quad \text{(Equation 2)} \] ### Step 4: Solve the Equations Now we have two equations: 1. \( 2x - 7y = 0 \) 2. \( 4x - 15y = -2 \) From Equation 1, we can express \( x \) in terms of \( y \): \[ 2x = 7y \implies x = \frac{7y}{2} \] ### Step 5: Substitute in the Second Equation Substituting \( x = \frac{7y}{2} \) into Equation 2: \[ 4\left(\frac{7y}{2}\right) - 15y = -2 \] This simplifies to: \[ 14y - 15y = -2 \implies -y = -2 \implies y = 2 \] ### Step 6: Find the Value of \( x \) Now that we have \( y = 2 \), we can find \( x \): \[ x = \frac{7(2)}{2} = 7 \] ### Step 7: Form the Two-Digit Number Now we can find the two-digit number: \[ 10x + y = 10(7) + 2 = 70 + 2 = 72 \] ### Final Answer Thus, the two-digit number is: \[ \boxed{72} \]
Promotional Banner

Topper's Solved these Questions

  • SIMULTANEOUS LINEAR EQUATIONS IN TWO VARIABLES

    ICSE|Exercise Topic 2 (4 Marks questions)|8 Videos
  • SIMULTANEOUS LINEAR EQUATIONS IN TWO VARIABLES

    ICSE|Exercise Topic 1 (4 Marks questions)|8 Videos
  • SIMULTANEOUS EQUATIONS

    ICSE|Exercise EXERCISE 6 (G)|13 Videos
  • SOLIDS

    ICSE|Exercise Exercise 21(C )|10 Videos

Similar Questions

Explore conceptually related problems

A two digit number is obtained by either multiplying sum of digits by 8 and adding 1 or by multiplying the difference of the digits by 13 and adding 2. Find the number.

A two digit number is obtained by either multiplying the sum of the digits by 8 and subtracting 5 or by multiplying the difference of the digits by 16 and then adding 3. Find the number.

A two-digit number is obtained by either multiplying the sum of the digits by 8 and then subtracting 5 or by multiplying the difference of the digits by 16 and then adding 3. Find the number.

The sum of a two digit number and the number obtained by reversing the order of its digits is 121, and the two digits differ by 3. Find the number.

The sum of the two-digit number is 9 The number formed by interchanging the order of the digits is 27 more than the given number.Find the number.

The sum of a two digit number and the number obtained on reversing the digits is 165. If the digits differ by 3, find the number.

The sum of a two digit number and the number obtained by reversing the order of its digits is 99. If the digits differ by 3, find the number.

A two-digit number is 3 more than 4 times the sum of its digits. If 18 is added to the number, the digits are reversed. Find the number.

The sum of the digits of a two-digit number is 9. If 27 is subtracted from the number, the digits get reversed. Find the number.