Respuesta :

the complete question in the attached figure

we know that
the ratio is 1:3
that means 
(1+3)=4 liters
To prepare 4 liters of fruit punch use 1 liter of orange juice and 3 liters of pineapple
so
to Make 3 Liters of fruit punch
the proportion to find the pineapple liters will be
3/4=x/3------> x=9/4-----> 2.25 liters of 
pineapple

the answer is
2.25 lt pineapple
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