Question

The sum of a 2 digit no and the no obtained by reversing
the order of its digits is 121. Also, the difference of the units digit and the ten digit is 3 Then, the numbers are​

Answer 1

let the digit at unit place be x

and the digit at ten's place be y

then the number will be = 10x + y

and the number obtained by reversing the digits be = 10x+y

now according to the given condition, we get

(10y+x) + (10x+y) = 121

x+y=11

also x-y=_+3 [ it is given that difference of the digit is 3]

x+y=11 (1; and x-y=3 .......(2)

adding (1) and (2) we get

2x=14 or x= 7

using x=7 in equation (¡) , we have

7+y=11

● y=11-7=4

therefore the number is 47

Next,

x+y=11.......(3)

x-y= -3......(4)

adding (3) and (4) we get,

2x=8

x=4

using x=4 in (i) we get y=11-4=7

so the number is 74

Hence the number is either 47 or 74