Question

A number consists of two digits whose sum is 9. if 27 is subtracted from the number its
digits are reversed. Find the number. 10 points​

Answer 1

Answer:-

Let the digit at ten's place be x and digit at one's place be y.

The number = 10x + y.

Given:

Sum of the digits = 9

⟶ x + y = 9

⟶ x = 9 - y -- equation (1).

And,

If 27 is subtracted from the number, the digits are reversed.

According to the above condition,

⟶ 10x + y - 27 = 10y + x

Substitute the value of x from equation (1)

⟶ 10(9 - y) + y - 27 = 10y + 9 - y

⟶ 90 - 10y + y - 10y + y = 27 + 9

⟶ - 18y = 36 - 90

⟶ y = - 54/ - 18

⟶ y = 3

Substitute the value of y in equation (1).

⟶ x = 9 - y

⟶ x = 9 - 3

⟶ x = 6

The number = 10(6) + 3 = 60 + 3 = 63.

∴ The required two digit number is 63.

Answer 2

$\huge \bf \pink \star \ \purple question$

A number consists of two digits whose sum is 9. if 27 is subtracted from the number its

digits are reversed. Find the number.

$\bf \ \star \: solution$

___________________________

Let me draw an equation.

Assume Z is the Numer and it was a two digit number so,

Z = x+10y

x + y = 9

Z - 27 = 10x + y

Z = 10x + y + 27

10x + y + 27 = x + 10y

27 = x + 10y -10x -y

9y -9x = 27

9(y-x) = 27

y - x = (27/9) = 3

x + y = 9

$\bf \pink \star\: add \: both \:$

2y = 12

y = 6

x + y = 9

x + 6 = 9

x = 3

$\bf put \: the \: value \: of \: x$

Z = 3 + (10*6)

Z = 3 + 60 = 63

Z = 63

_______________

Hope the above equation will solve many problem by just passing different values -:-)