sonya spent 2/5 of her money and then had $18 left. how much money did she originally have?

3/5x = 18

x = 18/(3/5)

x = 18 ( 5/3)

x = 90/3

x = 30

30

To solve this problem, we need to set up an equation. Let's assume that Sonya originally had "x" dollars.

According to the problem, Sonya spent 2/5 of her money, which means she had (1 - 2/5) = 3/5 of her money left.
We're also given that she had $18 left, so we can create the equation:

(3/5) * x = $18

To solve for x, we'll multiply both sides of the equation by 5/3 to isolate x:

(5/3) * (3/5) * x = $18 * (5/3)

The 3/5 and 5/3 will cancel each other out:

x = $18 * (5/3)

Calculating this, we find:

x = $30

Therefore, Sonya originally had $30.