Answer:
Stratified sampling
Step-by-step explanation:
Samples may be classified as:
Convenient: Sample drawn from a conveniently available pool.
Random: Basically, put all the options into a hat and drawn some of them.
Systematic: Every kth element is taken. For example, you want to survey something on the street, you interview every 5th person, for example.
Cluster: Divides population into groups, called clusters, and each element in the cluster is surveyed.
Stratified: Also divides the population into groups. However, then only some elements of the group are surveyed.
In this question:
Population divided into groups, and random samples are drawn from the groups. This is a mark of stratified sampling.
Answer: This question doesn't have an answer.
Step-by-step explanation:
1/2+ 1/4
= 2/4+ 1/4
= 3/4
1/12+ 1/6
= 1/12+ 2/12
= 3/12
= 1/4
Therefore, 1/4+ 1/6+ 1/12
= (1/12+ 1/6)+ (1/12+ 1/6)
= 2*(1/12+ 1/6)
= 2* (1/4)
= 2/4
= 1/2
Hope this helps~
Answer:
(5, 9)
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtract Property of Equality
<u>Algebra I</u>
- Solving systems of equations using substitution/elimination
Step-by-step explanation:
<u>Step 1: Define Systems</u>
x - 5y = -40
18x - 5y = 45
<u>Step 2: Rewrite Systems</u>
18x - 5y = 45
- Multiply both sides by -1: -18x + 5y = -45
<u>Step 3: Redefine Systems</u>
x - 5y = -40
-18x + 5y = -45
<u>Step 4: Solve for </u><em><u>x</u></em>
<em>Elimination</em>
- Combine equations: -17x = -85
- Divide -17 on both sides: x = 5
<u>Step 5: Solve for </u><em><u>y</u></em>
- Define equation: x - 5y = -40
- Substitute in <em>x</em>: 5 - 5y = -40
- Isolate <em>y</em> term: -5y = -45
- Isolate <em>y</em>: y = 9
