Answer:
Probability that the sample mean comprehensive strength exceeds 4985 psi is 0.99999.
Step-by-step explanation:
We are given that a random sample of n = 9 structural elements is tested for comprehensive strength. We know the true mean comprehensive strength μ = 5500 psi and the standard deviation is σ = 100 psi.
<u><em>Let </em></u>
<u><em> = sample mean comprehensive strength</em></u>
The z-score probability distribution for sample mean is given by;
Z = 
~ N(0,1)
where, 
= population mean comprehensive strength = 5500 psi
= standard deviation = 100 psi
The Z-score measures how many standard deviations the measure is away from the mean. After finding the Z-score, we look at the z-score table and find the p-value (area) associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X.
Now, Probability that the sample mean comprehensive strength exceeds 4985 psi is given by = P( > 4985 psi)
P( > 4985 psi) = P( > 
) = P(Z > -15.45) = P(Z < 15.45)
= <u>0.99999</u>
<em>Since in the z table the highest critical value of x for which a probability area is given is x = 4.40 which is 0.99999, so we assume that our required probability will be equal to 0.99999.</em>
Answer:
X < -9
Step-by-step explanation:
5a +18 < -27
5a < -27 -18
5a < - 45
5a/5 < - 45/5
a < - 9
Answred by Gauthmath
Answer:
Total amount of fencing needed as an algebraic expression in terms of x is: <em>10x</em><em> </em><em>+</em><em> </em><em>3</em> .
Step-by-step explanation:
As it is given that each rectangle has the same dimensions, the dimensions of each rectangle must be: x units by 2x + 1 units.
Based on this, we can calculate the total amount of fencing needed.
Let width of each rectangle = x
Let length of each rectangle = 2x + 1
There are 4 widths and 3 lengths in total of fencing.
Therefore:
= 4 ( x ) + 3 ( 2x + 1 )
Expand:
= 4x + 6x + 3
Group like-terms:
= 10x + 3
Answer:
1. 80
2. 2400
Step-by-step explanation:
1. what is the change in Dan's total pay for each copy of math is fun he sells?
2. what is Dan's total pay if he doesn't sell any copies of math is fun?
Given
y=80x + 2400
When x=0
y=80(0)+2400
=0+2400
=2400
When x=1
y=80x + 2400
=80(1) + 2400
=80+2400
=2480
change in Dan's total pay for each copy of math is fun he sells is
= 2480 - 2400
=80
2. Dan's total pay if he doesn't sell any copies of math is fun?
y=80x+2400
When x=0
y=80(0)+2400
=0+2400
=2400
I am 95% sure the answer is C
