Answer:
Z = -1.2 ( It is below the group mean), The sudent performed less than average.
Step-by-step explanation:
From the question,
Applying
Z = (x-μ)/σ........................ Equation 1
Where Z = z-score, x = observed score or raw score, μ = mean of the score, σ = standard deviation of the score
Given: x = 55 marks, μ = 70, σ = 12
Substitute these values into equation 1
Z = (55-70)/12
Z = -15/12
Z = -1.25
Hence the z- score is negative, meaning it is below the group mean, I.e the student who get 55 marks, performed less than average
Answer:
with which one
Step-by-step explanation:
Whats the question tell me and i'll try to help
Answer:
C = 10(pi) yards
A = 25(pi) yards
Step-by-step explanation:
<u>Answer:</u>
-10,1,19
<u>Step-by-step explanation:</u>
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x+y+z = 10 (Equation 1)
2y-x= 12 (Equation 2)
x-y+2z = 7 (Equation 3)
(Equation 2): -x = -2y+12
x = 2y-12 (Equation 4)
(Equation 1) - (Equation 3): 2y-z = 3
-z = -2y+3
z = 2y-3 (Equation 5)
Substitute (4) and (5) into (1)
x+y+z = 10
(2y-12)+y+(2y-3) = 10
5y-15 = 10
5y = 5
y=1
Substitute y=1 into (2)
2y-x= 12
2(1)-x= 12
2-x= 12
-x= 12-2
-x= 10
x= -10
Substitute y=1 and x=-10 into (1)
x+y+z = 10
-10+1+z = 10
z-9 = 10
z = 10+9
z = 19
Order: x = -10, y = 1, and z = 19
