Respuesta :
In order to explain how to do direct variations proportions, let's use the following example:
"Two apples have a cost of $3. So what is the cost of six apples?"
In this problem, if the number of apples increase, the cost also increases (in the same proportion), so we have a direct variation proportion.
The proportion of the cost and the number of apples is always the same, so we can write:
[tex]\begin{gathered} \frac{\text{ cost1}}{\text{ number1}}=\frac{\text{ cost2}}{\text{ number2}} \\ \frac{3}{2}=\frac{x}{6} \end{gathered}[/tex]Where x represents the cost we want to find. So after writing this equation with fractions, we can solve for x:
[tex]\begin{gathered} 3=\frac{2\cdot x}{6} \\ 3=\frac{x}{3} \\ x=3\cdot3 \\ x=9 \end{gathered}[/tex]So the final cost for six apples is $9.
