Answer:
C
Step-by-step explanation:
Question: 10 - 8 = 2
A = (-18)
B = 18
C = 2
D = (-2)
Population = 135 students
Mean score = 72.3
Standard deviation of the scores = 6.5
Part (a): Students from 2SD and 3SD above the mean
2SD below and above the mean includes 95% of the population while 3SD includes 99.7% of the population.
95% of population = 0.95*135 ≈ 129 students
99.7% of population = 0.997*135 ≈ 135 students
Therefore, number of students from 2SD to 3SD above and below the bean = 135 - 129 = 6 students.
In this regard, Students between 2SD and 3SD above the mean = 6/2 = 3 students
Part (b): Students who scored between 65.8 and 72.3
The first step is to calculate Z values
That is,
Z = (mean-X)/SD
Z at 65.8 = (72.3-65.8)/6.5 = 1
Z at 72.3 = (72.3-72.3)/6.5 = 0
Second step is to find the percentages at the Z values from Z table.
That is,
Percentage of population at Z(65.8) = 0.8413 = 84.13%
Percentage of population at (Z(72.3) = 0.5 = 50%
Third step is to calculate number of students at each percentage.
That is,
At 84.13%, number of students = 0.8413*135 ≈ 114
At 50%, number of students = 0.5*135 ≈ 68
Therefore, students who scored between 65.8 and 72.3 = 114-68 = 46 students
Answer:
70 gallons
Step-by-step explanation:
I know there are 4 quarts in a gallon, so divide the given quarts amount by 4!
280 ÷ 4 = 70.
Search "gallon conversion chart" on a search engine to find some helpful images!! :)
Answer:
the first function is correct
Answer:
2x + 6y ≤ 120
Step-by-step explanation:
From the above question, we are told that: No more than 120 lb of sausage links and briskets will be cooked on the grill.
Let
x = Number of sausage links
y = Number of Briskets
The word NO MORE THAN means less than or equal to 120 lb and this word is represented by the inequality sign:
≤
Sausage links = 2 lb each
Briskets = 6 lb each
The inequality =
2lb × x + 6lb × y ≤ 120lb
2x + 6y ≤ 120
Therefore, the inequality represents all possible combinations of x, the number of sausage links that will be cooked on the grill, and y, the number of briskets that will also be cooked is given as:
2x + 6y ≤ 120
