hmmm let hmm come to think..5£ is a bit too much for some junk glass anyway =) hehee, anyhow. so 5cents then
let us nevermind the price for now, and see how many grams are needed for the 6hours
so 1 bottle (500 grams), gives Adam 7.5 minutes of oven time
how many grams will it be for 6hrs or 6 * 60 = 360 minutes?
[tex]\bf \begin{array}{ccllll}
grams&minutes\\
\textendash\textendash\textendash\textendash\textendash\textendash&\textendash\textendash\textendash\textendash\textendash\textendash\\
500&7.5\\
x&360
\end{array}\implies \cfrac{500}{x}=\cfrac{7.5}{360}
\\\\\\
\textit{that'll give you, }\boxed{?}\textit{ grams of glass for 6hrs}\\\\
\textit{divide by 1000 to make it Kgs}\implies \cfrac{\boxed{?}}{1000}Kgs
\\\\\\
\textit{is 5cents per Kgs of glass, so }\cfrac{\boxed{?}}{1000}\cdot 5[/tex]
that's how many "p" (pennies? pence? pounds?) will it be for 6hrs of oven time for Adam
