Question

Choose the equation that is equivalent to this statement. 90 is 70% of x

Answer 1

Greetings! 

We can create an equation that can be used to solve problems of this kind:
$90= (\frac{70}{100})x$
Let x represent the number.

Solve for x.
$90= \frac{70}{100}x$

Divide both sides by $\frac{70}{100}$
$\frac{90}{\frac{70}{100}}= \frac{\frac{70}{100}x}{\frac{70}{100}}$

$(\frac{90}{1})({\frac{100}{70}})=x$

$\frac{9000}{70}=x$

Reduce the fraction to lowest terms or a decimal
$\frac{900}{7}=x$

The Answer Is:
$\left[\begin{array}{ccc} x=\frac{900}{7}\end{array}\right]$

70% of $\frac{900}{7}$ is equal to 90.

Hope this helps!
-Benjamin