You buy

You buy two soft drinks and 24 toffees at the tuck shop. One soft drink costs six times as much as one toffee, so your total purchase cost is R54. Determine the cost of one toffee.

Correct answer:

t =  1.5

Step-by-step explanation:

$$\begin{gathered} 2d+24t=54 \\ d=6t \\ 2\cdot d+24\cdot t=54 \\ d=6\cdot t \\ 2d+24t=54 \\ d-6t=0 \\ Row2-\frac{1}{2}\cdot Row1\to Row2 \\ 2d+24t=54 \\ -18t=-27 \\ t=\frac{-27}{-18}=1.5 \\ d=\frac{54-24t}{2}=\frac{54-24\cdot 1.5}{2}=9 \\ d=9 \\ t=\frac{3}{2}=1.5 \end{gathered}$$

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