Question

One number is 10 times as large as another, and their difference is 81. Find the numbers.

If x represents the smaller number, then the larger number is
10
10x
X - 10​

Answer 1

90

Explanation:

10x - x = 81

9x = 81

x = 9

larger number = 10 x 9 = 90

Answer 2

For this case we have that "x" is the variable that represents the smallest number to find. Let and the variable that represents the largest number, then:
`y = 10x\\y-x = 81`

Substituting the first equation in the second:

`10x-x = 81\\9x = 81\\x = \frac {81} {9}\\x = 9`

So, the biggest number is:

`y = 10 * 9 \\y = 90`

Answer:

10x

90