Question

Solve the equation.

A number consists of two digits whose sum is equal to 8. When 18 is added to the number, the digit interchange their places. Find the number

Answer 1

Original Number:

Let digit in the one's place be x

so the digit in the tens place will be (8-x)

Hence, the number=10(8-x)+x=80-10x+x=80-9x

New number:

Interchanging the digits

Digit in one's place=(8-x)

Digit in tens place=x

Hence, the number=10(x)+(8-x)=10x-x+8=8+9x

A/q

80-9x+18=8+9x

=>90=18x

=>x=5

Hence,Original number=80-9x=80-45=35

Ans=35