A number lying between 10 and 100 is seven times the sum of its digits – InterviewSolution

1.	A number lying between 10 and 100 is seven times the sum of its digits.If 9 is substracted from it,the digis of tigits of thenumber are reversed. Then the number is :
Answer» suppose number is 10x+yso 10x+y=7(x+y)so 3x=6yso x=2y10x+y-9=10y+x20y+y-9=10y+2yso 9y=9so y=1 and x=2so number is 21

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