Answer:
5 gallons of water must be added.
10 gallons to start with
adding 'x' gallons of water final volume = 10 + x
.9 (10) = amount of vinegar
.1(10) = amount of water
amount of vinegar before and after water addition is constant
.9(10) = .6(10+x)
9 = 6 + .6x
3 = .6x
x = 5 gallons of water to be added
(i truly hope i helped you
Answer:

Step-by-step explanation:
we know that
Brenda requires 480 grams of couscous for 4 people
so
using proportion
Find out how many grams of couscous she requires for 14 people
Let
x -----> the amount of grams

Answer: r=(-189)
first you subtract both sides by 8 and get -21=r/9
then you multiply 9 with each side and get -189 = r
you can check by rewriting the problem with -189 as r and solving the equation
Putting it in simpler terms