Question

the digit of a two digit number differ by three. if the digits are inter change and the resulting number is added to the original number we get 143 .what is the original number

Answer 1

Let the two digit no be 10x +y
A. To. Q
x-y=3------------------(1)
10y+x +10x+y =143
11x+11y=143
x+y=13-----------------(2)
Eq(1)+eq(2)
2x=16
x=8
Put x in eq (2)
y=5
So reqd no is 85