Respuesta :
4 gallons=3 weeks
12 weeks/3 weeks = 4
4 gallons X 4 groups of 3= 16
Hope this helps....k
12 weeks/3 weeks = 4
4 gallons X 4 groups of 3= 16
Hope this helps....k
Answer: 9 gallons
Step-by-step explanation:
We can see that the quantity of shampoo and the number of weeks a re directly proportional.
We know that if two quantities x and y are directly proportional , then we have the following equation :-
[tex]\dfrac{x_1}{y_1}=\dfrac{x_2}{y_2}[/tex]
Let x be the total quantity of shampoo need for 12 weeks , then we have
[tex]\dfrac{x}{12}=\dfrac{4}{3}\\\\\Rightarrow\ x = \dfrac{4\times12}{3}\\\\\Rightarrow\ x =16[/tex]
If she has 7 gallons of shampoo, then the required quantity of shampoo for 12 weeks = [tex]16-7=9[/tex]
Hence, she must order 9 gallons of shampoo if she wants to have enough for 12 weeks.