Question

- The sum of the digits of a two-digit number is 7. The number obtained by interchanging the digits eneses
the original number by 27. Find the number
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Answer 1

AnSwEr -:

The original number will be 25

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Let digit at ones place=x

and ,

Digit at tens place= y= 10 x y= 10y

So,

The number will be 10y + x

x + y = 7 ........ (1)

According To question

Interchanging of digits -:

As ,

10x + y

So,

(10x+y)-(10y-x)=27

9x-9y=27

x-y=3 ....(2)

Adding equation (1) and (2)

2x=10

x=5

substituting in equation (1)

y=7-5

=2

The original number-: 10y + x

Y= 2

X= 5

10 x 2 + 5

= 25

Thus the original number will be 25

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Answer 2

Step-by-step explanation:

required no. 10x+y. reversed no. 10y+x

let the first digit of no. be x and the second digit be y.

x+y=7 ........(1)

x=7-y

1 0y+x= 10x+y +27

9y -9x = 27

dividing the whole equation by 9, we get

y-x=3......(2)

substituting the value of x in eq (2)

y- (7-y) = 3

2y -7 =3

2y= 10

therefore, y = 5

substituting the value of y , we get

x= 7-5

= 2

therefore the required no. is 25

HOPE THIS HELPED