Algebrahard · Past Paper
The sum of digits of a two-digit number is 12. The number obtained by interchanging the digits exceeds the given number by 18. Find the number.
A57
B75
C48
D84
✓ Correct Answer: A — 57
x+y=12. (10y+x)-(10x+y)=18 -> 9y-9x=18 -> y-x=2. Solving gives y=7, x=5. Number is 57.
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