The cost for each book will be
if the person buy 7 books.
Further explanation:
The arithmetic sequence can be expressed as follows,
......
Here,
represents the first term,
represents the second term, and so on.
The common difference “d” can be obtained as follows,
![\boxed{d = {a_2} - {a_1}}](https://tex.z-dn.net/?f=%5Cboxed%7Bd%20%3D%20%7Ba_2%7D%20-%20%7Ba_1%7D%7D)
The nth term can be obtained as follows,
![\boxed{{a_n} = a + \left( {n - 1} \right)d}](https://tex.z-dn.net/?f=%5Cboxed%7B%7Ba_n%7D%20%3D%20a%20%2B%20%5Cleft%28%20%7Bn%20-%201%7D%20%5Cright%29d%7D)
Explanation:
The cost of a book is ![\$ 17.55.](https://tex.z-dn.net/?f=%5C%24%2017.55.)
The cost of a book is
if the person buys 2 books.
The cost of a book is
if the person buys 3 books.
The cost of a book is
if the person buys 4 books.
The sequence is ![\$ 17.55, \$ 16.70, \$ 15.85, \$ 15.00.](https://tex.z-dn.net/?f=%5C%24%2017.55%2C%20%5C%24%2016.70%2C%20%5C%24%2015.85%2C%20%5C%24%2015.00.)
The first term is
the second term is ![\$ 16.70.](https://tex.z-dn.net/?f=%5C%24%2016.70.)
The common difference “d” can be obtained as follows,
![\begin{aligned}d&={a_2} - {a_1}\\&=16.70 - 17.55\\&=- 0.85\\\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7Dd%26%3D%7Ba_2%7D%20-%20%7Ba_1%7D%5C%5C%26%3D16.70%20-%2017.55%5C%5C%26%3D-%200.85%5C%5C%5Cend%7Baligned%7D)
The cost for each book if the person buys 7 books can be obtained as follows,
![\begin{aligned}{a_6}&= 17.55 + \left( {7 - 1} \right)\left( { - 0.85} \right)\\&= 17.55 + 6\left({ - 0.85} \right)\\&= 17.55 - 5.1\\&=\$12.45\\\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%7Ba_6%7D%26%3D%2017.55%20%2B%20%5Cleft%28%20%7B7%20-%201%7D%20%5Cright%29%5Cleft%28%20%7B%20-%200.85%7D%20%5Cright%29%5C%5C%26%3D%2017.55%20%2B%206%5Cleft%28%7B%20-%200.85%7D%20%5Cright%29%5C%5C%26%3D%2017.55%20-%205.1%5C%5C%26%3D%5C%2412.45%5C%5C%5Cend%7Baligned%7D)
The cost for each book will be
if the person buy 7 books.
Learn more:
1. Learn more about inverse of the functionhttps://brainly.com/question/1632445.
2. Learn more about equation of circle brainly.com/question/1506955.
3. Learn more about range and domain of the function brainly.com/question/3412497
Answer details:
Grade: Middle School
Subject: Mathematics
Chapter: Arithmetic Sequence
Keywords: Store, books, price, $17.55, 2 books, 3 books each cost $16.40, pattern continues, cost, 7 books.