Smoothie 2

David is using 100 ml of pineapple juice to make a smoothie.
He needs to use a pineapple juice to orange juice ratio of 2: 5.
How much orange juice should he use?

Correct answer:

o =  250 ml

Step-by-step explanation:

$$\begin{gathered} p=100\text{ml} \\ p:o=2:5 \\ o:p=5:2 \\ o=p\cdot \frac{5}{2}=100\cdot \frac{5}{2}=\frac{100\cdot 5}{2}=\frac{500}{2}=250\text{ml} \end{gathered}$$

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