Rosie works 40 hours a week as an office manager. if she made $23,920 last year, how much was she paid per hour?

Hey there.. 
Lets solve this questions in steps..

Step 1 - we need to know that how many weeks are there in 1 year
so, there are 52.17 weeks but the round figure is 52 weeks.

Step 2 - we know that shawn worked 40 hours a week
So, in order to get total hour worked by him in one year, we need to multiply 52 * 40
i.e. 52 *40 = 2080

Step 3 - Now, we have total hours we can simply divide the total hour worked with how much he earned last year
i.e. 23,920 / 2080
 = $11.5 per hour.

Hope this helped you..  :)