Question

one of the two whole number is 8 times the other if the sum is 81 find the number​

Answer 1

Answer:

let the whole number be x

thus the second number is 8x

According to the given condition

8x+x=81

9x=81

x=81/9

x=9

Answer 2

$\red\bigstar$Answer:

$\boxed{\sf x\: =\: 9\:}$

$\blue\bigstar$ Given:

• One of the two whole number is 8 times of the other.
• The sum of both is 81.

$\pink\bigstar$To find:

• The unknown numbers

$\red\bigstar$ Solution:

Let the unknown number be x.

$\hookrightarrow$ $\therefore$The first unknown number is x

Now the other number

$\hookrightarrow$ 8 × x

$\hookrightarrow$ 8x

It is given that the sum of both the numbers :

$\hookrightarrow$ 81

A/q x + 8x = 81

$\implies$ 9x = 81

$\implies$ x = $\sf\dfrac{81}{9}$

$\implies$$\boxed{\sf x\: =\: 9\:}$

$\boxed{\sf\therefore x\: =\: 9\:}$

So the unknown numbers are :

• $\boxed{\sf 9}$
• 8x = 8 × 9 = $\boxed{\sf 72}$

$\green\bigstar$ Verification:

It is given that,

x + 8x = 81

By substituting the values of x, we get:

$\implies$ 9 + 8(9) = 81

$\implies$ 9 + 72 = 81

$\implies$ LHS = RHS

Hence Verified too.

$\blue\bigstar$ Concepts Used:

• Assumption of the Unknown numbers
• Equation of expressions
• Transposition Method

$\pink\bigstar$Extra - Information:

• What is linear Equation?

$\hookrightarrow$ Linear equations are equations having variables with power 1.

• Some methods to solve linear Equation :

$\hookrightarrow$ Method of substitution

$\hookrightarrow$ Cross multiplication method

$\hookrightarrow$ Method of elimination

$\hookrightarrow$ Matrix method

$\hookrightarrow$ Determinant methods