Barter exchange calculation

We can exchange three bananas for four oranges in a barter shop, and nine bananas are obtained for four pineapples. How many oranges do we get for one pineapple?

Final Answer:

p =  3

Step-by-step explanation:

$$\begin{gathered} 3:4=b:p \\ 4:9=a:b \\ a=1 \\ b=9/4\cdot a=9/4\cdot 1=\frac{9}{4}=2\frac{1}{4}=2.25 \\ p=b\cdot 4/3=2.25\cdot 4/3=3 \end{gathered}$$

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