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#1 2006-12-21 17:30:10

balasvce
Member
Registered: 2006-12-20
Posts: 37

solve

34) if there are x red roses and y yellow roses and each rose

costs $8 and each yellow rose costs $3,what is the cost of red roses in a bouquet of $80.

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#2 2006-12-21 17:45:31

pi man
Member
Registered: 2006-07-06
Posts: 251

Re: solve

Assuming you meant to say each RED rose costs $8...

You have 8x + 3y = 80.   x and y have to be integers since you're not going to buy your lovely wife/mom/girlfriend a half of a rose.   So now your just try out some numbers.   If you buy one $8 rose, that leaves $72 for 24 yellow roses.   So that's one possibility. 

If you buy 2 red roses for $16, that leaves $64 dollars for 21.333 yellow roses.   No good.
If you buy 3 red roses for $18, that leaves $56 dollars for 18.666 yellow roses.   No good.
If you buy 4 red roses for $24, that leaves $48 dollars for 16 yellow roses.   Good.

Continue this and hopefully you'll pick up the pattern.  You can buy the following bouquets for $80:

1 red and 24 yellow
4 red and 16 yellow
7 red and 8 yellow
10 red and 0 yellow

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