Question

SHOW THE EQUATION YOU SET UP10% of what number is 90?

Answer 1

Recall that the x% of y can be computed using the following expression:

`y\cdot(x)/(100)\text{.}`

Now, let n be the number such that its 10% is 90, then we can set the following equation:

`90=n\cdot(10)/(100)\text{.}`

Simplifying the above equation we get:

`90=(1)/(10)n\text{.}`

Multiplying the above equation by 10 we get:

`\begin{gathered} 90*10=(1)/(10)n*10, \\ n=900. \end{gathered}`

Answer:

Equation:

`(1)/(10)n=90.`

Number: 900.