A cross beam in a highway bridge experiences a stress of 14 ksi due to the dead weight of the bridge structure. When a fully loa
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Answer:
probability P = 0.32
Explanation:
this is incomplete question
i found complete A manufactures makes integrated circuits that each have a resistance layer with a target thickness of 200 units. A circuit won't work well if this thickness varies too much from the target value. These thickness measurements are approximately normally distributed with a mean of 200 units and a standard deviation of 12 units. A random sample of 17 measurements is selected for a quality inspection. We can assume that the measurements in the sample are independent. What is the probability that the mean thickness in these 16 measurements x is farther than 3 units away from the target value?
solution
we know that Standard error is expess as
Standard error =
Standard error =
Standard error = 3
so here we get Z value for 3 units away are from mean are
mean = -1 and + 1
so here
probability P will be
probability P = P( z < -1 or z > 1)
probability P = 0.1587 + 0.1587
probability P = 0.3174
probability P = 0.32
Answer:
Δx = 25 ft.
Explanation:
Assuming that the person on the ground starts running at the same time as the egg is dropped, we have two simultaneous trajectories:
1 ) Egg falling:
If the egg is dropped, and we neglect the air resistance, we can use the kinematic equation that relates the distance and fall time, as follows:
yf-y₀ = 1/2* g* t²
If we take the up direction as positive, we can solve for t as follows:
0-100 ft = 1/2* (-32.15 ft/s²)* t²
⇒ t = = 2.5 sec.
2) Person on the ground running away:
In order to be able to run away, and then return to catch the egg, running at constant speed, he must run during exactly the half of the time that the egg is falling, i.e., 1.25 sec.
We can get the distance at which he can reach, applying the definition of velocity:
v = (xf-x₀) / (tfi-t₀)
If we choose t₀=0 and x₀ = 0 , we can solve for xf, as follows:
xf = v*t = 20 ft/sec*1.25 sec = 25 ft.