a)
P( X<86)
I know that, z = (X-mean)/(sd)
z1 = (86-120)/20) -1.7000
hence,
P( X<86) =P(Z<-1.7)
NORMSDIST(-1.7) = 0.0446
b)
P(80 < X < 100)
= P(X<100) - P(X<80)
I know that, z = (X-mean)/(sd)
z1 = (80-120)/20) = -2.0000
z2 = (100-120)/20) = -1.0000
hence,
P(80 < X < 100)= = P(Z<-1) - P(Z<-2)
= NORMSDIST(-1) - NORMSDIST(-2) = 13.59%
c)
z= NORMSINV(0.4)
z= -0.253347103
I know that, z = (X-mean)/sd
(X-mean)/sd = -0.2533
X= -0.2533*20+120
X= 114.93
d)
P(Z<z) 10%
z= NORMSINV(0.1)
z= -1.281551566
I know that, z = (X-mean)/sd
(X-mean)/sd = -1.2816
X= -1.2816*20+120
X= 94.37
7. Hint for c and d: given P(X S x) a percentage, we have P(Z Sz)the...
etX be normally distributed with mean μ = 120 and standard deviation σ = 20. (a) Find z such that P(X > z) = 0.90. (b) Find z such that P(80 S X 100).
Please show steps by step on how to get answer. Thank you, experts. Save & Exit 5 Let X be normally distributed with mean u = 120 and standard deviation o = 20. [You may find it useful to reference the z table.] 3.33 points a. Find PX < 86). (Round "z" value to 2 decimal places and final answer to 4 decimal places.) Skipped P(XS 86) eBook References b. Find P180 SX S100). (Round "z" value to 2 decimal...
x-μ 6. Hint: use the formula*. If X falls within a range, transform both lower and upper limits. Let X be normally distributed with mean deviation σ 4 a. Find P(X30). b. Find P(X> 2), c. Find P(4 <X< 10). d. Find P(6 <X< 14) 10 and standard
X is normally distributed with mean μ= 5.2 and standard deviation σ= 1.4. A. Find the z-score corresponding to X= 7.3. B. Compute P(X≤7.3) C. Compute P(X>7.3)
We can now use the Standard Normal Distribution Table to find the probability P(-0.25 sz s 1). 0.05 0.06 0.07 0.08 0.09 -0.2 0.4013 0.3974 0.3936 0.3897 0.3859 0.00 0.01 0.02 0.03 0.04 Using these 1.0 0.8413 0.8438 0.8461 0.8485 0.8531 The table entry for z = -0.25 is 0.00 and the table entry for z = 1 is values to calculate the probability gives the following result. PC-0.25 sz s 1) P(Z < 1) - P(Z 5 -0.25) 10....
The random variable X is normally distributed. Also, it is known that P(X > 173) = 0.04. [You may find it useful to reference the z table.] a. Find the population mean μ if the population standard deviation σ = 10. (Round "z" value to 3 decimal places and final answer to 2 decimal places.) b. Find the population mean μ if the population standard deviation σ = 17. (Round "z" value to 3 decimal places and final answer to...
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