Question

If y varies directly as x and z, and y= 8/3 when x = 1 and 2 = 4, find y when x = 6 and z = 3.

Answer 1

`\begin{gathered} y\propto x,y\propto z \\ So,\text{ } \\ y=k_1x,\Rightarrow(8)/(3)=k_1*1\Rightarrow k_1=(8)/(3) \\ y=k_2z\Rightarrow(8)/(3)=k_2*4\Rightarrow k_2=(2)/(3) \\ \text{Now, } \\ y=k_1x\Rightarrow(8)/(3)*6=16 \\ y=k_2x\Rightarrow(2)/(3)*3\Rightarrow2 \end{gathered}`