Question

a two digit number is such that the sum of its digit is 9.On adding 9 to the number the digits are reversed.Find the number

Answer 1

let the no. be x
and solve by yourself

Answer 2

x+y=9---(1)
(10x+y)+9=10y+x
9x+9=9y
x+1=y
x-y=-1
from 1
9-y-y=-1
2y=10
y=5
x=9-y
    9-5
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