Answer:
You must watch minimum of 200 movies per month for the DVD player purchase to be a smart purchase.
Step-by-step explanation:
Let assume that you watch 100 movies in a month:
For going to theater:
$9 × 100 = $900
For renting movies and using the DVD Player:
Renting = $5 × 100 = $500
DVD Player cost: $400
Total spent in a month = $500 + $400 = $900
Therefore, in a month, the amount spent going to theater = the amount spent using DVD Player and renting the Film.
Let assume you watch 200 movies in a month:
For going to theater:
$9 × 200 = $1800
For renting movies and using the DVD Player:
Renting = $5 × 200 = $1000
DVD Player cost: $400
Total spent in a month = $1000 + $400 = $1400
Therefore, amount spent using DVD Player and renting movies is cheaper than going to theater to watch movies in a month.
It is safe to conclude that for the DVD Player to be a smart purchase by you, you must watch minimum of 200 movies in a month.