[tex]\frac{28}{9}[/tex] liters do they drink in 4 days.
The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.
According to the question
John's family drinks 7/9 of milk a day.
Liters do they drink in 4 days: X
Using unitary method
X = [tex]\frac{7}{9} \times4[/tex]
X = [tex]\frac{28}{9}[/tex]
[tex]\frac{28}{9}[/tex] liters do they drink in 4 days.
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