Let x be the number of MP3 players TechWiz sold last week.
If TechWiz sold in total 130 MP3 and DVD players, then it sold (130-x) DVD players.
1. TechWiz Electronics makes a profit of $35 for each MP3 player sold, then it makes a profit $35x for x MP3 players sold.
2. TechWiz Electronics makes a profit of $18 for each DVD player sold , then it makes a profit $18(130-x) for (130-x) DVD players sold.
3. An expression for the combined total profit (in dollars) TechWiz made from MP3 and DVD players last week is
35x+18(130-x).
You can simplify it:
35x+2,340-18x=17x+2,340
Answer: 35x+18(130-x) or 17x+2,340
2.25h(60m/hr)(1/3)=45m
So Rick spends 45 minutes studying math per night.

. Subtract 10x from both sides.

. Divide by 5 on both sides. x=20. So you would need to buy 20 movies.
Answer:
I would rather use their multiples.
Step-by-step explanation:
With 13 and 14, neither number has many factors (and few prime factors, for that matter) so factoring would be pretty much useless. If you wanted to use the prime factors of 14 (7 and 2) multiplying either of them by 13 would not give you the LCM. Actually the LCM is just 13*14 which is 182.
Good luck!
Answer:
I would go with the second one.
Step-by-step explanation: