Milk cream mixture

I want to turn to help with the following example.
How do I reach an 8% solution?
I need to mix 3.5% milk with 33% cream.
Thank you for being so helpful.

Final Answer:

r =  50:9

Step-by-step explanation:

$$\begin{gathered} r=a:b \\ 0.035\cdot a+0.33b=0.08(a+b) \\ 0.035\cdot r\cdot b+0.33b=0.08(r\cdot b+b) \\ 0.035\cdot r+0.33=0.08\cdot (r+1) \\ 0.045r=0.25 \\ r=\frac{0.25}{0.045}=5.55555556 \\ r=\frac{50}{9}\doteq 5.555556 \\ r=5.5556\approx 5.5556=50:9 \end{gathered}$$

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