Question

The sum of the digits of a2 digits number is 10.the number obtained by interchanging the digits exceeds the original number by 36.find the number

Answer 1

Let the one digit be y. Let the ten's digit be x. Original no. be 10x+y. Reverse no. be 10y+x.     x+y=10        ....(i)     =10x+y+36=10y+x     =9x-9y=-36     =x-y=-4     =x=y-4         ....(ii)  Substitute eq.(ii) into eq.(i),we get    =y-4+y=10    =2y=14    =y=7 Put y=7 into eq.(ii),we get      x=7-4      x=3 original no. is 10x+y      =10×3+7      =37