Answer:
Natalie Spent $59.54 on songs after 5 months at online music service. 
 
Step-by-step explanation: 
 Total membership cost =$14.99 
 
Number of songs purchased in each month = 9 
 
Cost per song = $0.99 
 
We need to find total amount she had spent after 5 months. 
 
Solution:- 
 
So First we will Number of songs purchased in 5 months. 
 
1 month = 9 songs 
 
So in 5 months = Songs purchased in 5 months. 
 
By Using Unitary method we get; 
 
Songs purchased in 5 months = 
 
Now Also Given: 
 
1 song = $0.99 
 
45 songs = Cost for 45 songs. 
 
Again by using Unitary method we get; 
 
Cost for 45 songs = 
 
No Total Amount Natalie spent after 5 months is equal to Total membership cost plus Cost of songs purchased in 5 months. 
 
framing in equation form we get; 
 
Total Amount Natalie spent = 
 
Hence Natalie Spent $59.54 on songs after 5 months at online music service.