3. A certain number between 10 and 100 is 8 times the sum of its digit – InterviewSolution

1.	3. A certain number between 10 and 100 is 8 times the sum of its digits, and if 45 be subtracted from it, thedigits will be reversed. Find the number.
Answer» Let the number be xyvalue of number = 10x+y10x+y = 8(x+y)10x+y =8x+8y2x-7y=0....................(1)10x+y-45 = 10y+x9x-9y=45x-y = 5.................(2)multiply by -2-2x+2y=-10add to (1)-5y=-10y=2x-y =5x=7Number = 72

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