Answer:
C)Systematic Random Sample
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 case:
Every kth element(in this exercise 10th) is systematic sample. So the answer is given by option c.
Answer:
Sarah is 13 years old
Step-by-step explanation:
Represent Sarah's age with S
Her first brother's age with F
Her second brother's age with B
So, we have:
From the first statement, we have:
---- (1)
From the second, we have:
---- (2)
The product of their ages is 40.
First, we make F the subject in (1) and B the subject in (2)


Their product is represented as follows:

Substitute values for F and B

Open bracket


Subtract 40 from both sides

Factorize:

Split:
or 
But Sarah's age can't be 0 because she has two younger brothers.
So, we stick to

Make S the subject

<em>Hence, Sarah is 13 years old</em>
Answer:
-1
Step-by-step explanation:
-2+(-1)÷3
-2-1÷3
-3÷3
-1
Answer:
y=1.5x
78
Step-by-step explanation:
y=1.5x
y=1.5(52)
y=78
Hello! I would love to help!
9. Basically, it is asking us to multiply 5.2 by 46.
5.2*46=239.2
So, your answer is 239.2 inches.
10. First, let's find out how many blocks she has left to run by subtracting the number of blocks she has already ran by the number of total blocks.
60-18=42
So Susan has 42 blocks left to run. Now, let's divide that by 2 since she can run 2 blocks per minute.
42/2=21
So, the answer is 21 minutes.
11. Let's set up an equation: We know that she will automatically pay $49.95 per month, plus $0.15 per additional minute. We also know her final total for the month was $61.20:
49.95+0.15m=61.20
Let's solve! Subtract both sides by 49.95
49.95+0.15m-49.95=61.20-49.95
Simplify
0.15m=11.25
Now, divide both sides by 0.15
0.15m/0.15=11.25/0.15
M=75
So your answer is 75 additional minutes.
Hope this helped! Comment if you have questions!