It takes 1 pound of flour to make y cakes. The price of flour is w dollars for x pounds. In terms of w, x and y, what is the dollar cost of the flour required to make 1 cake?

Question

anonymous · Answer

A. xy/w
B. y/wx
C. w/xy
D. wx/y
E. wxy

solomonzelman · Answer

Lets just simply write the data for convenience:
$\large\color{black}{ \displaystyle 1{~} {\rm pound}= y{~} {\rm cakes} }$
$\large\color{black}{ \displaystyle  {\rm $}w= x{~} {\rm pounds} }$
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1 cake is ?

anonymous · Answer

make it up?

anonymous · Answer

5 cakes?

solomonzelman · Answer

excuse me, the cost for 1 cake (not flour)

solomonzelman · Answer

lets do it as it is:

$\large\color{black}{ \displaystyle  {\rm $}w= x{~} {\rm pounds} }$

$\large\color{black}{ \displaystyle  {\rm $}\frac{w}{x}= 1{~} {\rm pounds} }$

you know that: `1 pound=y cakes` and thus,

$\large\color{black}{ \displaystyle  {\rm $}\frac{w}{xy}= \frac{1}{y} {~} {\rm pounds}=1{~\rm cake}  }$

solomonzelman · Answer

because if  `1 pounds = y cakes`
then,   `1/y  pounds = 1 cake`