Question

the sum of the digits of two digit number is 11.The given number is less than the number obtained by interchanging the digits by 9.Find the number.​

Answer 1

Answer:

let the digits are x ,y

x+y=11..........................1st

so the no is 10x+y

(10x+y)-9=10y+x.........2nd

10x+y-9-10y-x=0

9x-9y=-9................2nd

by elemination,

9(x+y=11)

9x-9y=-9 after addition we get ,

18x=2

x=2

x+y=9

2+y=9

y=7

so no. is (10x+y)

10*2+7=27