Question

Sum of the digits of a two digit no. Is 12 new number formed by reversing the digit is greater than the original number by 54 find the original number

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

Let one’s digit be x.

Since the sum of digits is 12.

Therefore, ten’s digit = (12 – x) ….(i)

∴Number = 10 x ten’s digit + One’s digit

= 10 (12 – x) + x

= 120 – 10x + x

= 120 – 9x

Now, if digits are reversed, then

One’s digit = 12 – x

and ten’s digit = x

∴ New number = 10 x ten’s digit + one’s digit

= 10(x) + 12 – x

= 10x + 12 – x

= 10x – x + 12

= 9x + 12

According to question,

⇒ 9x + 12 = (120 – 9x) + 54

⇒ 9x + 12 = 120 + 54 – 9x

⇒ 9x + 12 = 174 – 9x

⇒ 9x + 9x = 174 – 12

⇒ 18x = 162

$\frac{162}{18}$

x = 9

one digit = 9

ten digit = 12 - 9 = 3

hence the requaried number = 39