At dorothy's hair salon, 4 gallons of shampoo will last 3 weeks. she has 7 gallons of shampoo. how much more must she order if she wants to have enough for 12 weeks? i will give brainliest

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 :-

Let x be the total quantity of shampoo need for 12 weeks , then we have

If she  has 7 gallons of shampoo, then the required quantity of shampoo for 12 weeks =

Hence, she must order 9 gallons of shampoo if she wants to have enough for 12 weeks.

your question is incomplete, write all the numbers in the sequence that it tells you.  

step-by-step explanation:

$119.20

step-by-step explanation:

$372.50 - 60% off is $149. $149-20% off is $119.20