Q10 of 71 Page 68

In a two digit number, the digit at tens place is 7 and the sum of the digits is 8 times the digit at unit place. Then the number is

Let the number be 10x + y where x is the digit at tens place and y is the digit at unit place.


According to the question,


x = 7


Sum of the digits = 7 + y


⇒ 7 + y = 8y


⇒ 7y = 7


⇒ y = 1


So, the number = 71

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