please help me with my work and please tell me how you got that answer?

Question

At Mr. Vid's video rentals you can join his VID Club for a monthly memebership fee of $30. Club memebers pay only 85cents to rent each movie. If you are not a member of the VID Club, the movies rent for $2.25 each. How many videos would you have to rent each month to make a membership worth the investment?

**Please dnt answer @ all if your not going to answer it rite,thank you

Answer 1

$30.00 / $2.25 = 13-1/3
So if you rented 14 movies in one month, the membership would be worth it. (14 x $2.25 = $31.50)
If you watch a movie at least every other night, it would be a good deal, but I wouldn't become a member. :)

Answer 2

OK.. then I won't answer it, but I will try to show you how to do it.

Lets solve it graphically.. thats an easy way and will give you an idea of how simultaneous equations (thats what these are) work.

You have two different conditions (what people pay WITH memberships and without.)

get a piece of graph paper and draw your x and y axis.

lets do the non members first.

1) Its the first of the month and you haven't spent any money. Lets make the vertical part Money and the horiz. videos..

2) Number the bottom from 1 to about 30 for now.. you can extend it if you need to

3) Lets do the $ part in $2 increments awkward but it is a best guess as I type this.

ok.. at the start, zero videos have cost you nothing.. so your line begins at the 0,0 axis

video #1 costs you 2.25.. so make an x on the 1video vert. line at about $2.25. Video #2 is another 2.25 makeing a total so far of 4.50 put your x there.. video #3, another 2.25 for a total so far of $6.75. Keep this up until you rent about 20 videos ($45) and connect the x's.. it will be a straight line (it better be or go back and check the ones that are not in line).

ok.. now lets do memberships.

almost the same thing except that members have to plunk down that $30,. so.. a zero videos you have already spent $30. Make your first x there (use a different color pencil). Ok... from here on it is easy...

Video #1 costs you $30.85 (membership plus the rental).. #2 is $31.70 (two rentals plus membership) and so on..

Do about 20 rentals ($30 membership plus $17 in rental fees) and connect the dots.

Do the lines cross yet? Where they cross is the break even point and renting one more video as a member is the point at which membership is a better deal.

Easy eh.. ? Pencil, graph paper, and simple math.

Now try it with equations:

$30 + x(.85) = x(2.25)

If the two ways match you have not only your answer but also learned your lesson...

..

Answer 3

Divide the cost of membership by the cost of renting. so $30.00 divide by .85 get no. of movies.