Question

A number consist of two digit whose some is 9.If the digit are reversed ,the new number is 3/8 of the first no. . find the number... linear equation one variable question​

Answer 1

Step-by-step explanation:

Given:

• The sum of two numbers

To Find:

• The Original Number

Solution:

Let unit's digit be x

$\therefore \tt \: ten's \: digit = 9 - x$

Original number=10(9-x)+x=90-10x+x=90-9x

Number after interchanging it's digits

=10(x)+9-x=10x+9-x=9x+9

Given is the the original number(first number) is 3/8 of the after number(number after interchanging it's digits).

So, the equation formed as-

$\tt \longrightarrow\frac{3}{8} (9x + 9) = 90 - 9x \\ \tt \longrightarrow3(9x + 9) = 8(90 - 9x) \\ \tt \longrightarrow27x + 27 = 720 - 72x \\ \tt \longrightarrow99x = 693 \\ \tt \longrightarrow \: x = 7$

Unit's digit=7

Ten's digit=9-x=9-7=2

ORIGINAL NUMBER=27