Question

One number is 1/4 of another number. The sum of the two numbers is 15. Find the two numbersUse a comma to separate your answers

Answer 1

Let x and y represent both numbers.

Given:

x = 1/4 * y

x + y = 15

Let's find the two numbers.

We have the system of equations:

`\begin{gathered} x=(1)/(4)y \\ \\ x+y=15 \end{gathered}`

Plug in 1/4y for x in the second equation:

`\begin{gathered} (1)/(4)y+y=15 \\ \\ \\ (5)/(4)y=15 \\ \\ 1.25y=15 \end{gathered}`

Divide both sides by 1.25:

`\begin{gathered} (12.5y)/(1.25)=(15)/(1.25) \\ \\ y=12 \end{gathered}`

Now, to solve for x plug in 12 for y in either the first or second equation.

Let's take the first equation:

`\begin{gathered} x=(1)/(4)y \\ \\ x=(1)/(4)*12 \\ \\ x=3 \end{gathered}`

Therefore, the numbers are:

3, 12

ANSWER:

3, 12