If `1957-a9=18b8` Then the sum of the digits a and b is

The difference of the digits of a two digit number is 8. Then the sum of the digits is

If the number obtained by interchanging the digits of a two digit number is 18 more than the original number and the sum of the digits is 8 then what is the original number?

If the number obtained on the interchanging the digits of two-digit number is 18 more than the original number and the sum of the digits is 8, then what is the Reversed number?

In a two-digit number, the sum of the digits is 9. If 9 is subtracted from the number, then the digits get reversed. Find the product of the digits

A book contains 1000 pages numbered consecutively. The probability that the sum of the digits of the number of a page is 9, is a/b, then a xx b =