Let's denote the tens digit as "x" and the units digit as "y".

From the problem, we know two things:

1) x + y = 9 (The sum of the digits is 9)

2) 10x + y - 63 = 10y + x (If 63 is subtracted from the number, its digits are interchanged)

Now, we can solve these equations step by step:

First, simplify the second equation:

9x - 9y = 63

Divide through by 9:

x - y = 7

Now we have a system of two equations:

x + y = 9

x - y = 7

Add these two equations together:

2x = 16

Divide by 2:

x = 8

Substitute x = 8 into the first equation:

8 + y = 9

Solve for y:

y = 1

So, the number is 81.

Question

Let's denote the tens digit as "x" and the units digit as "y".

From the problem, we know two things:

1) x + y = 9 (The sum of the digits is 9)

2) 10x + y - 63 = 10y + x (If 63 is subtracted from the number, its digits are interchanged)

Now, we can solve these equations step by step:

First, simplify the second equation:

9x - 9y = 63

Divide through by 9:

x - y = 7

Now we have a system of two equations:

x + y = 9

x - y = 7

Add these two equations together:

2x = 16

Divide by 2:

x = 8

Substitute x = 8 into the first equation:

8 + y = 9

Solve for y:

y = 1

So, the number is 81.

Knowee AI · Accepted Answer

Let's denote the tens digit as "x" and the units digit as "y".

From the problem, we know two things:

1) x + y = 9 (The sum of the digits is 9)

2) 10x + y - 63 = 10y + x (If 63 is subtracted from the number, its digits are interchanged)

Now, we can solve these equations step by step:

First, simplify the second equation:

9x - 9y = 63

Divide through by 9:

x - y = 7

Now we have a system of two equations:

x + y = 9

x - y = 7

Add these two equations together:

2x = 16

Divide by 2:

x = 8

Substitute x = 8 into the first equation:

8 + y = 9

Solve for y:

y = 1

So, the number is 81.

A number consists of two digits. The sum of digits is 9. If 63 is subtracted from the number, its digits are interchanged. Find the number