Answer:
cost = 1.35n
$33.75 for 25 songs
Step-by-step explanation:
Based on the numbers given, the cost is proportional to the number of songs downloaded. The constant of proportionality is the cost of one song: 1.35.
cost = 1.35n
For 25 songs, ...
cost = 1.35·25 = 33.75 . . . . dollars
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The equation is ...
cost = 1.35n
