Number System
If the of a two-digit number are interchanged, the number so obtained is greater than the original number by 18. If the sum of the two digits of the number is 14. What is the original number ?
Let the no. be 10x + y.No. formed by the interchange of digits = 10y + xWe have y - x = 2 .........(i)y + x = 14 .........(ii)Solving (i) and (ii), we get x = 6, and y = 8∴ the no. is 68.
If the sum of the digits of a number is divisible by 9, the number will be divisible by 9.2 + 6 + 3 + 2 + 5 + 1 = 19The nearest multiple of 9 is 18.19 - 18 = 1.
EXAMIANS