Question

quessons.
1.
The sum of digits of a 2-digit number is 9. If 27 is subtracted from the number we
get a 2-digit number with the sequence of digits changed. Find the number.​

Answer 1

Step-by-step explanation:

Hence, The two-digit number =10x+y⇒10×6+3=63.

Answer 2

Answer:

The other way to solve it is using simultaneous equations, where two generic equations are formed in x and y where x and y are the two digits.

Here sum is sum of the two digits and difference is the difference between the number and its reverse.

x + y = sum … (1)

10 * x + y = 10 * y + x + difference

9 * x - 9 * y = difference

9 * (x - y) = difference

x - y = difference / 9 … (2)

Putting values we get

x + y = 9 … (1)

x - y = 27 / 9 = 3 … (2)

Solving (1) and (2)

we get x = 6 and y = 3

Therefore the numbers are 63 and 36.