Saved Bookmarks
| 1. |
The sum of digit of a two digit number is 12. the number obtained by inter changing the digit exceeds the given number by 18 .find the number |
|
Answer» LET the TENS digit be x and the UNITS digit be y. So the number=10x+y A.q. x+y=12 x=12-y (equation 1) After interchanging the number we get =10y+x Also, (10y+x)-(10x+y)=18 10y+x-10x-y=18 9y-9x=18 9(y-x)=18 y-x=18/9 y-x=2 From eauation 1 x=12-y So, y-(12-y)=2 y-12+y=2 2y=12+2 2y=14 y=14/2 y=7 And x=12-y =12-7 =5 Hence the number is 57. |
|