Answer: 5.37
Step-by-step explanation:
Let x = ACT scores.
Given: ACT scores have a mean of 20.8 and 9 percent of the scores are above 28. The scores have a distribution that is approximately normal.
i.e. P(X>28)=0.09 (i)
Now,
![P(X>28)=P(\dfrac{X-\mu}{\sigma}>\dfrac{28-20.8}{\sigma})\\\\= P(z>\dfrac{7.2}{\sigma})\ \ \ \ [z=\dfrac{X-\mu}{\sigma}]](https://tex.z-dn.net/?f=P%28X%3E28%29%3DP%28%5Cdfrac%7BX-%5Cmu%7D%7B%5Csigma%7D%3E%5Cdfrac%7B28-20.8%7D%7B%5Csigma%7D%29%5C%5C%5C%5C%3D%20P%28z%3E%5Cdfrac%7B7.2%7D%7B%5Csigma%7D%29%5C%20%5C%20%5C%20%5C%20%5Bz%3D%5Cdfrac%7BX-%5Cmu%7D%7B%5Csigma%7D%5D)
(ii)
One -tailed z value for p-value of 0.09 =1.3408 [By z-table]
From (i) and (ii)
Hence, the standard deviation = 5.37
Answer:
12 shirts
Step-by-step explanation:
If a T-Shirt Launcher can launch 6 shirts in 30 minutes, that means it can launch 12 shirts in an hour, because there are 60 minutes in a hour, and 30 minutes is half os 60 minutes, so we just do 6 x 2 = 12.
Answer:
The height of the toy is 9 feet after 1 second
Step-by-step explanation:
we have
where
h(t) is the toys height from the ground
t is the time in seconds
so
For t=1 sec
substitute the value of t in the quadratic equation and solve for h(t)
Answer:
Step-by-step explanation:
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