SATMathematics Practice Test 1

To determine the price per pound of beef when it was equal to the price per pound of chicken, determine the value of x (the number of weeks after July 1) when the two prices were equal.
The prices were equal when $\mathit{b}=\mathit{c}$; that is, when $2.35+0.25\mathit{x}=1.75+0.40\mathit{x}$.
This last equation is equivalent to $0.60=0.15\mathit{x}$, and so $\mathit{x}=\frac{0.60}{0.15}=4$.
Then to determine b, the price per pound of beef, substitute 4 for x in $\mathit{b}=2.35+0.25\mathit{x}$, which gives $\mathit{b}=2.35+0.25\left(4\right)=3.35$ dollars per pound.
Choice A is incorrect.
It results from using the value 1, not 4, for x in $\mathit{b}=2.35+0.25\mathit{x}$. Choice B is incorrect.
It results from using the value 2,not 4, for x in $\mathit{b}=2.35+0.25\mathit{x}$. Choice C is incorrect.
It results from using the value 3, not 4, for x in $\mathit{c}=1.75+0.40\mathit{x}$.