Answer:
a. z-score = -1.2
b. The age 23 years old is -1.2 standard deviations below the mean
c. The age is not unusual
Step-by-step explanation:
a. Transformation to z-score
Mathematically;
z-score = (x - μ)/σ
where σ and μ are the standard deviation and the mean respectively.
From the question, x = 23, μ = 27.2 and σ = 3.5
Let’s put these into the equation;
z-score = (23-27.2)/3.5 = -1.2
b. Interpretation of result
The interpretation is that 23 years old is -1.2 standard deviations below the mean
c. Determination
The age is not unusual. This is because any z-value below -2 or above 2 is considered unusual
-1.2 is above -2 and thus it is not unusual
Answer:
9x
Step-by-step explanation:
Since you are subtracting a negative from a positive you would get 9
5A + 7 = 3A + 7 + 2A
We need to solve for A.
3A + 7 + 2A = 3A + 2A + 7 = 5A + 7 (We can add 3A and 2A because it's the same variable, so we add the coefficients)
5A + 7 = 3A + 7 + 2A
5A + 7 = 5A + 7
5A + 7 is always equal to 5A + 7 because it's the same equation. So the equation got infinitely many solutions.
Answer:
y = 6x² -13x -5
Step-by-step explanation:
(1,-12) (2,-7) (5,80)
y = ax² + bx + c
-12 = a*1² + b*1 + c = a+b+c (1)
-7 = 4a + 2b + c (2)
80 = 25a + 5b + c (3)
(2)-(1): 3a + b = 5 (4)
(3)-(2): 21a + 3b = 87 (5)
(4)*3: 9a + 3b = 15 (6)
(5)-(6): 12a = 72 a = 6
(4) b = -13
(2) c = -5