An MP3 player costs $70 and song downloads cost $0.85 each. How do you write an expression that represents the cost of the MP3 player and x number of downloaded songs. Then find the total cost if 20 songs are downloaded?

Question

Savannah Anderson · Accepted Answer

The expression is

#70+0.85n#

For #n=20# this works out to #$87$

The $70 cost of the mp3 player is a fixed expense. We do not need a variable to express it. We create a variable to represent the number of songs we purchase and multiply it by the price of each song to determine how much we spend on music downloads. The total cost is obtained by adding the two terms.

Eli Assouline · Answer

See the solution process below:

The following is the expression for this MP3 player's total cost of ownership: #M = p + cx# Where: #M# is the Total Cost of Ownership for the MP3 player. #p# is the cost to buy the MP3 player - $70 in this case #c# is the cost of a CD - $0.85 in this case #x# is the number of CDs purchased - 20 for the problem we are asked to solve. When you substitute, you get: #M = $70 + ($0.85 xx 20)# #M = $70 + $17# #M = $87#

Eva Adamson · Answer

undefined The expression representing the cost of the MP3 player and $ x $ number of downloaded songs is:

$$ \text{Total cost} = 70 + 0.85x $$

To find the total cost if 20 songs are downloaded:

$$ \text{Total cost} = 70 + 0.85 \times 20 $$

$$ \text{Total cost} = 70 + 17 $$

$$ \text{Total cost} = 87 $$

So, the total cost if 20 songs are downloaded is $87.