While shopping, lucinda spent $48. if the amount she spent was 15% of her savings, how much savings did she have before shopping?

15% is the same as 
We can simplify this fraction by dividing by 5 from both the numerator and the denominator. 
 ÷  = 
Now we know that part of the money Lucinda spent is 15%.
Since it wasn't her total money and only part of it, 48 will be the numerator.
We are trying to find the total amount of savings (her total money)
Now we can create a proportion.

48 ÷ 3 = 16
Now multiply the numerator and denominator by 16 :)
 ×  = 
And yes the answer is 320 since that was the total amount of money spent
Hope this helped! :)