Answer:
-1?
Step-by-step explanation:
Answer:
(64,86.5)
Step-by-step explanation:
find the case where he gets 70 and the case where he gets 79
if his average is 70:
(75+62+85+2x)/5=70
(222+2x)/5=70
222+2x=350
2x=128
x=64
if his average is 79:
(75+62+85+2x)/5=79
(222+2x)/5=79
222+2x=395
222+2x=395
2x=173
x=86.5
The solution to the equation is x = 0, 2
The graph is posted
hope that helps :)
Answer:
8
Step-by-step explanation:
You just gotta divide 64 by 8
The expected completion time is μ = 40 weeks.
The random variable, X = 38 weeks (the probable time)
If the standard deviation is σ, then the z-score is z = (x - μ)/σ.
Let us test the given standard deviations.
When σ=1,
z = (38-40)/1 = -2
From standard tables,
P(x<=38) = P(z<=-2) = 0.0228 =2.3%
When σ=2,
z = (38*40)/2 = -1
P(x<=38) = P(z<=-1) = 0.1587 = 15.9%
When σ=4,
z = (38-40)/4 = -0.5
P(x<=38) = P(z<=-0.5) = 0.3085 = 30.9%
Answers:
z=1 => 2.3%
z=2 => 16% (approx)
z=4 => 31% (approx)
