When it comes to sampling methods, random sampling is one of the most effective. The principal wants the results of his or her sample to be as fair as possible, so it is best to choose students randomly, and in a neutral environment. The mall is not a neutral environment because not all students have access to the mall, and even those who do are not guaranteed to provide accurate results. The same goes for a basketball game, and student council. Samples taken from these environments are likely to produce more bias. However, collecting a survey from every tenth student entering the school one morning is more likely to produce accurate results that are representative of the school population.
Assuming that the mix disolves into the 20 gallons and doesn't take up space
1:2
x:20
1/2=x/20
multiply btoh sides by 20
10=x
answer is 10 cups of mixture
Answer:
a) 910
b) 828100
c) 144320
Step-by-step explanation:
a. ∑y
This is the sum of all values of y. So

b. (∑y)^2
This is the square of the sum, so the square of 910, that we found in the previous item.
910² = 828100
c. ∑y^2
This is the sum of the squares of each amount spent. So

Answer:
D. 4in, 12in
Step-by-step explanation:
Area of triangle = 24in²
Unknown:
Base and height of the triangle = ?
Solution:
The area of a triangle =
x base x height
From the problem,
base =
x height
let the base = b
height = h
b =
h
h = 3b
Input into the formula of area;
24 =
x b x 3b
Mulitply through by 2;
48 = 3b²
b² = 16
b = √16 = 4
So, h = 3b= 3 x 4 = 12in