Question

what is the original valve​

Answer 1

Answer:

92

Step-by-step explanation:

original no: 10x+y

interchanging : 10y+x

given :10y+x=4(10x+y)-24

39x-6y=24.......( eq.1)

given unit digit exceeds tens digit by 7 written as

y-x=7........(eq.2)

solving eq's 1& 2

y=9

x=2(i.e., 29)

checking by verifying condition..,

92=29*4-27