Question

the sum of the digit of a two digit number is 15 if the number formed by the reversing the digits is less than the original number by 27 find the original number check your solution

Answer 1

Sol:
Let the number with two digits be 10x + y.
Sum of the digits is 15.
⇒ x + y = 15 ----------------- (1)
Number formed by reversing the digits = (10y + x)

(10x + y) - (10y + x) = 27
⇒ 9x - 9y = 27
⇒ x - y = 3 ----------------- (2)
Solving equations (1) and (2), we get x = 9 and y = 6.

Therefore, the original number is 10(9) + 6 = 96.

Answer 2

let the no. of the 2 digits be 10x+y
sum of the digits is 15
therefore,
x+y=15-----》1

no formed by reversing the digit =(10y+x)
(10x+y )-(10y+x)=27
9x - 9y = 27------》2
equation 2 dividing by 3
3x-3y=9------》3
again dividing it by 3
x-y=3------》4

solving by 1 and 4
x=9
y=6
the original no is 10x+y
=》10(9)+6
=》90+6
=》96