Techwiz electronics makes a profit of $35 for each mp3 player sold and $18 for each dvd player sold. last week, techwiz sold a combined total of 113 mp3 and dvd players.
let x be the number of mp3 players techwiz sold last week. write an expression for the combined total profit (in dollars) techwiz made from mp3 and dvd players last week.

According to question conditions;

Number of MP3 players = x

While combined numbers of both MP3 and DVD players = 113

So number of DVD players = 113 – x

Profit on single MP3 player = $35

Profit on single DVD player = $18

Total profit on all MP3 player = ($35)(x) (1)

Total profit on all DVD player = ($18)(113 – x) (2)

Combined profit from MP3 and DVD players are obtained by adding both equations (1) and (2), i.e.

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