Question

One of the two digits of a two digit number is three times the other digit. If you interchange the digits of this two digit number and add the resulting number to the original number, you get 132. What is the number?

Answer 1

Let two digits number be xy.

» One of the two digits of a two digit number is three times the other digit.

» 3x = y

Now, It's time to consider tenth and ones place.

» 10x + y

→ 10x + 3x

→ 13x

» If you interchange the digits of this two digit number.

» 10y + x

→ 10(3x) + x

→ 30x + x

→ 31x

Finally, Add the resulting numbers to the original number.

→ 13x + 31x = 132

→ 44x = 132

→ x = 132/44

→ x = 3

» 3x = y

→ 3 × 3 = y

→ y = 9

Hence,

The Original numbers will be 39 (xy).

Answer 2

Answer:

Let two digits number be xy.

» One of the two digits of a two digit number is three times the other digit.

» 3x = y

Now, It's time to consider tenth and ones place.

» 10x + y

→ 10x + 3x

→ 13x

» If you interchange the digits of this two digit number.

» 10y + x

→ 10(3x) + x

→ 30x + x

→ 31x

Finally, Add the resulting numbers to the original number.

→ 13x + 31x = 132

→ 44x = 132

→ x = 132/44

→ x = 3

» 3x = y

→ 3 × 3 = y

→ y = 9

Hence,

The Original numbers will be 39 (xy).