Respuesta :
- She has initially 120songs
If she adds songs new in constant amount like 2 per week
Then it will form an arithmetic sequence.
- Where common difference is d
Answer:
[tex]f(w)=116+4w[/tex]
Step-by-step explanation:
Question
Iris has 120 songs on her playlist. Each week, she downloads 4 new songs. Write an expression to show the total number of songs on Iris's playlist after [tex]w[/tex] weeks.
Solution
This scenario can be modeled as an arithmetic sequence since Iris is adding a constant number of songs to her playlist each week.
Arithmetic sequence
General form of an arithmetic sequence: [tex]a_n=a+(n-1)d[/tex]
where:
- [tex]a_n[/tex] is the nth term
- a is the first term
- d is the common difference between terms
We are told that she starts with 120 songs on her playlist, so [tex]a=120[/tex]
We are told that she adds 4 new songs each week, so [tex]d=4[/tex]
Also, [tex]n=w[/tex]
Substituting these values into the formula:
[tex]\implies a_w=120+(w-1)4[/tex]
[tex]\implies f(w)=116+4w[/tex]