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.
Answer:
Yes it is true
Step-by-step explanation:
15/10 equals 1.5
Answer:
Option A is correct.
Step-by-step explanation:
As we see the graph, we can say that the correct statement is :
A.)All repairs requiring 1 hour or less have the same labor cost. We can see that the coat from 0 hours to 1 hour is $50. So, the number of hours falling in this range has the same repairing cost.
B.) Labor costs the same no matter how many hours are used for a repair. This is wrong as the graph is increasing after 1 hour.
C.) Labor costs for a repair are more expensive as the number of hours increases. This is wrong as the hours are increasing from 0.25 to 0.5 then to 0.75 but they all have the same cost.
D.)There is no cost of labor for a repair requiring less than 1 hour. This is also wrong. The cost is $50.
Answer: option C is the correct answer
Step-by-step explanation:
The system of linear equations is
10x + 7y = 12 - - - - - - - 1
8x + 7y = 18 - - - - - - - 2
Since the coefficient of y is the same in equation 1 and equation 2, we will eliminate y by subtracting equation 2 from equation 1, it becomes
10x - 8x + 7y - 7y = 12 - 18
2x = -6
x = - 6/2 = - 3
Substituting x = - 3 into equation 1, it becomes
10×-3 + 7y = 12
-30 + 7y = 12
Let the constants be on the right hand side and the term containing y be on the left hand side. It becomes
7y = 12 + 30
7y = 42
y = 42/7
y = 6
C) (−3, 6)
