SOLUTION: Please help me with these..I'm beginning courses and don't even know where to begin! 9/6=x/8 If the total cost of x apples is b cents, what is a general formula for the cos

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: Please help me with these..I'm beginning courses and don't even know where to begin! 9/6=x/8 If the total cost of x apples is b cents, what is a general formula for the cos      Log On


   

Question 143682: Please help me with these..I'm beginning courses and don't even know where to begin!
9/6=x/8
If the total cost of x apples is b cents, what is a general formula for the cost, in cents, of y apples?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Remember that a%2Fb=c%2Fd means that ad=bc.

Likewise, 9%2F6=x%2F8+ means that 9%2A8=+6%2Ax
72=6x

Divide both sides by 6: 72%2F6=%286x%29%2F6
12=x

You can generalize this to say x%2Fb=y%2F%28cents%29, and solve for "cents." Does this make "cents" to you ???

x%2Fb=+y%2F%28cents%29+ means that x%2A%28cents%29+=+yb

Solve for "cents": +cents+=+%28yb%29%2Fx

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